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Effects of post annealing on the microstructure,precipitation behavior,and mechanical property of a(CoCrNi)_(94)Al_(3)Ti_(3)medium-entropy alloy fabricated by laser powder bed fusion

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Journal of Materials Science & Technology 2023年第4期135卷 142-155页

作者： Zhuang Li Pengcheng Zhao Tiwen Lu Kai Feng Yonggang Tong Binhan Sun Ning Yao Yu Xie bolun han Xiancheng Zhang Shantung Tu Key Laboratory of Pressure Systems and Safety Ministry of EducationSchool of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237China Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China College of Automobile and Mechanical Engineering Changsha University of Science and TechnologyChangsha 410114China

The additive manufacturing of multi-principal element alloys has remarkable potential for industrial *** this study,a(CoCrNi)_(94)Al_(3)Ti_(3)medium-entropy alloy(MEA)with adequate strength-ductility synergy was prepared via laser powder bed *** microstructural evolution,mechanical property,and deformation mechanisms of the MEA were investigated after post annealing for a short period(0.5 h)at a temperature range of 773-1373 K using various microstructural characterization techniques and quantitative *** static recrystallization temperature of the(CoCrNi)_(94)Al_(3)Ti_(3)MEA ranged from 973 to 1073 *** average grain size first decreased and then increased,while the dislocation den-sity persistently decreased and texture gradually weakened with increasing annealing ***-richσ-phase precipitates formed after 1073 K and then gradually dissolved at 1373 K,while Ni,Al,and Ti elements were aggregated to form a small amount of fine L1_(2)coherent precipitates with an aver-age diameter of approximately 70 nm at 1373 *** evolution of the dislocation density,grain size,and precipitates significantly influenced the propensity of deformation twins and stacking faults,which consequently affected the strain hardening behavior and mechanical *** quantitative calcu-lation of strengthening mechanisms showed that dislocation strengthening played a dominant role at annealing temperatures below 1073 K,and it significantly weakened at 1373 *** and grain boundary strengthening both markedly increased owing to the formation of precipitation particles and recrystallization-induced grain refinement after annealing at 1073 K.

关键词： Medium-entropy alloy Additive manufacturing Heat treatment Strengthening mechanism Microstructural evolution

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不同化学生态型紫苏的镉耐性及镉富集能力研究

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农业环境科学学报 2021年第10期40卷 2106-2113页

作者：韩博伦肖清铁谢惠玲游武郑新宇林瑞余福建农林大学生命科学学院福建省农业生态过程与安全监测重点实验室福州350002 福建农林大学生命科学学院福建省作物生态与分子生理重点实验室福州350002

为探究不同化学生态型紫苏的镉耐性与镉富集能力差异,设置不同浓度镉处理,测定了4种化学生态型紫苏种子的萌发指标及其幼苗的镉含量与镉富集特性。结果显示,10.0 mg·L^(-1)镉处理对PKPA型、EK型和PK-I型紫苏种子的发芽率、发芽势无显... 详细信息

为探究不同化学生态型紫苏的镉耐性与镉富集能力差异,设置不同浓度镉处理,测定了4种化学生态型紫苏种子的萌发指标及其幼苗的镉含量与镉富集特性。结果显示,10.0 mg·L^(-1)镉处理对PKPA型、EK型和PK-I型紫苏种子的发芽率、发芽势无显著影响,但显著抑制了PK-Ⅱ型紫苏种子的萌发。不同浓度镉处理下,不同生态型紫苏各部位的镉含量均表现为:根(1052.0~5337.1 mg·kg^(-1))>茎(327.6~807.9 mg·kg^(-1))>叶(104.8~343.3 mg·kg^(-1)),全株镉含量在348.1~1416.73 mg·kg^(-1),远高于镉超富集植物的标准(100 mg·kg^(-1))。不同生态型紫苏的镉富集系数(BCF)存在显著差异,PAPK型、PK-Ⅱ型、EK型紫苏的BCF在2.0 mg·L^(-1)镉处理时最高,依次为252.0、300.5、295.3,显著高于PK-Ⅰ型,后者的BCF在5.0 mg·L^(-1)镉处理时最高(265.5),显著高于PAPK型、PK-Ⅱ型和EK型。不同生态型紫苏的镉富集量均以5.0 mg·L^(-1)镉处理时最高,PK-Ⅰ型紫苏镉总富集量为454.0μg·株-1,分别是PAPK型、PK-Ⅱ型和EK型的2.48、1.69倍和2.05倍。不同化学生态型紫苏的镉耐性间存在显著差异,镉胁迫下PK-Ⅰ型紫苏具有较高镉耐性及镉富集能力,可用于后续研究紫苏镉耐性作用机制以及镉污染稻田修复的主要种质资源。

关键词：紫苏化学生态型镉耐性镉富集作用

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紫苏分支酸合成酶PeCS基因克隆、生物信息学及原核表达分析

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分子植物育种 2024年第7期22卷 2089-2097页

作者：韩博伦肖清铁文欢欢律其鑫郑新宇林瑞余福建农林大学生命科学学院福建省农业生态过程与安全监测重点实验室福州350002 福建农林大学生命科学学院福建省作物生态与分子生理重点实验室福州350002

本研究旨在探究紫苏(Perilla frutescens L.)药用活性成分酚酸生物合成途径中的关键基因。基于前期紫苏转录组测序数据,筛选出酚酸合成途径中的差异表达基因分支酸合成酶(chorismate synthase, CS)基因,获得PeCS基因开放阅读框(ORF),利... 详细信息

本研究旨在探究紫苏(Perilla frutescens L.)药用活性成分酚酸生物合成途径中的关键基因。基于前期紫苏转录组测序数据,筛选出酚酸合成途径中的差异表达基因分支酸合成酶(chorismate synthase, CS)基因,获得PeCS基因开放阅读框(ORF),利用生物信息学技术对Pe CS基因功能做出初步预测,构建pET30a-PeCS原核表达载体,并转化大肠杆菌BL21 (DE3),IPTG诱导表达后进行SDS-PAGE检测。通过实时荧光定量PCR(RT-qPCR)技术检测紫苏不同组织(根,茎,叶)中PeCS表达水平。克隆得到紫苏PeCS基因开放阅读框(ORF)长度为877 bp,编码291个氨基酸,生物信息学预测为亲水性蛋白,定位于叶绿体。该蛋白相对分子质量为31 659.16。Pe CS基因编码蛋白不含信号肽且无跨膜区,亚细胞定位于叶绿体。所构建pET30a-PeCS原核表达载体在大肠杆菌BL21 (DE3)中表达的最适条件为15℃、0.5 mmol/L IPTG培养16 h,PeCS重组蛋白主要以包涵体形式存在,蛋白分子量与预测相符。RT-qPCR分析显示PeCS基因在紫苏不同器官组织中均有表达,且在叶中的表达量最高,在茎中表达量最低。本研究成功克隆紫苏分支酸合成酶PeCS基因,有助于更深入地阐释紫苏酚酸合成途径和调控机制。

关键词：紫苏分支酸合成酶生物信息学分析原核表达

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Optimal predictive sliding-mode guidance law for intercepting near-space hypersonic maneuvering target

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Chinese Journal of Aeronautics 2022年第4期35卷 320-331页

作者： bolun ZhanG Di ZHOU School of Astronautics Harbin Institute of TechnologyHarbin 150001China

The design of optimal guidance law for intercepting a near-space hypersonic maneuvering target with bounded inputs is considered. Firstly, a maneuvering model for near-space hypersonic aircraft is given. Then, the aircraft acceleration prediction can be obtained using this model with two neural networks. By using the target acceleration prediction, which is taken into account when calculating the Zero Effort Miss(ZEM), an optimal sliding-mode guidance law is proposed to fulfill the guidance task. An adaptive sliding-mode switch term is designed to deal with actuator saturation and prediction errors. Finally, numerical simulations show that the proposed guidance law can reduce the energy consumption and the terminal acceleration command of the interceptor effectively.

关键词： Adaptive sliding-mode control Near-space hypersonic aircraft Neural networks Optimal control Predictive guidance law

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Optimization Design of RC Ribbed Floor System Using Eagle Strategy with Particle Swarm Optimization

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Computers, Materials & Continua 2020年第1期62卷 365-383页

作者： Jiejiang Zhu bolun Zhou Department of Civil Engineering Shanghai UniversityShanghai200444China

The eagle strategy algorithm is combined with particle swarm optimization in this *** new algorithm,denoted as the ES-PSO,is implemented by interfacing Etabs structural analysis ***-PSO is used to optimize the RC ribbed floor system,including floor and underground garage *** considering the effects of reinforcement,the principle of virtual work is applied to calculate the deflections of *** cost is taken as the objective function and the constraint conditions are required to ***,the optimal layout,the optimal sections of the beams and slabs and the corresponding reinforcements are obtained for different column *** this investigation,the RC ribbed floor system is optimized according to the Chinese standard,whose column grids are 8.4 m and 8.4 *** performance of the ES-PSO algorithm is good enough,which can be applied to practical *** paper can also provide a basis for subsequent optimization design of monolithic structures.

关键词： Eagle strategy discrete variable floor system the principle of virtual work Optimum design Random walk

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Determination of the acidic properties of carboxylated carbocatalysts in an acid-catalyzed ring-opening reaction using kinetic profiling

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Nano Research 2017年第9期10卷 2954-2965页

作者： bolun Wang Guodong Wen Dangsheng SU Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Hefei 230026 China Department of Inorganic Chemistry Fritz Haber Institute of the Max Planck Society Berlin 14195 Germany

The acid-catalyzed ring-opening reaction of styrene oxide was used as a probe reaction for evaluating the acidic properties of carboxylated carbocatalysts. Significant discrepancies in the initial reaction rates were normalized using the total number of carboxyl groups, and demonstrated that the average catalytic activities of the carboxyl moieties on the carbocatalysts differed. Comparisons between the apparent activation energy E a and the pre-exponential factor A, derived from Arrhenius analysis, demonstrated that A varied more significantly, and therefore had a more significant effect on the reaction rates than E a. The variation in the calculated pKa values of the carboxyl groups was attributed to the electronic effects of the nitro groups. This hypothesis was supported by the temperature programmed desorption profiles of nitrogen monoxide ions.

关键词： carboxylated carbocatalysts acidic properties ring-opening reaction Arrhenius analysis pKa values electronic effect

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Computational fluid dynamics simulation of hydrodynamics in the riser of an external loop airlift reactor

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Particuology 2016年第4期14卷 95-101页

作者： Xuedong Jiang Ning Yang bolun Yang Department of Chemical Engineering State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an 710049 China Center for Mesoscience and State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China

Local hydrodynamics in the riser of an external loop airlift reactor （EL-ALR） are identified and the performances of three drag models are evaluated in computational fluid dynamics simulation. The simulation results show that the Schiller-Naumann drag model underestimated the local gas holdup at lower superficial gas velocity whereas the Tomiyama drag model overestimated that at higher superficial gas velocity. By contrast, the dual-bubble-size （DBS）-local drag model gave more reasonable radial and axial distri-butions of gas holdup in all cases. The reason is that the DBS-local drag model gave correct values of the lumped parameter, i,e., the ratio of the drag coefficient to bubble diameter, for varying operating conditions and radial positions. This ratio is reasonably expected to decrease with increasing superficial gas velocity and be smaller in the center and larger near the wall. Only the DBS-local drag model correctly reproduced these trends. The radial profiles of the axial velocity of the liquid and gas predicted by the DBS-local model also agreed well with experimental data.

关键词： Computational fluid dynamics External loop airlift reactor Drag model Gas holdup Mnltiscale Mesoscale

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Variable structure multiple model fixed-interval smoothing

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Chinese Journal of Aeronautics 2023年第2期36卷 139-148页

作者： bolun ZhanG Yongxin GAO Zhansheng DUAN Faculty of Electronic and Information Engineering School of Automation Science and EngineeringXi’an Jiaotong UniversityXi'an 710049China

This paper focuses on fixed-interval smoothing for stochastic hybrid *** the truth-mode mismatch is encountered,existing smoothing methods based on fixed structure of model-set have significant performance degradation and are *** develop a fixedinterval smoothing method based on forward-and backward-filtering in the Variable Structure Multiple Model(VSMM)framework in this *** propose to use the Simplified Equivalent model Interacting Multiple Model(SEIMM)in the forward and the backward filters to handle the difficulty of different mode-sets used in both filters,and design a re-filtering procedure in the model-switching stage to enhance the estimation *** improve the computational efficiency,we make the basic model-set adaptive by the Likely-Model Set(LMS)*** turns out that the smoothing performance is further improved by the LMS due to less competition among *** results are provided to demonstrate the better performance and the computational efficiency of our proposed smoothing algorithms.

关键词： Fixed-interval smoothing Model-set adaptation Multiple model estimation Smoothing algorithm Variable structure

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镉污染条件下水稻对假单胞菌TCd-1微生物修复的生理响应

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生态学报 2022年第5期42卷 1924-1933页

作者：文欢欢郑新宇肖清铁汪敦飞律其鑫韩博伦王玉洁樊荣荣游武郭尤睿钱鑫林瑞余福建省农业生态过程与安全监控重点实验室福建农林大学生命科学学院福州350002 作物生态与分子生理学福建省高校重点实验室福建农林大学福州350002

微生物在修复重金属污染土壤中发挥重要作用。为阐明假单胞菌TCd-1降低水稻镉吸收的机理,通过加镉土培盆栽试验,在10 mg/kg镉处理下,对比研究了接种菌株对2种镉耐性不同水稻品种(特优671、百香139)镉含量、根系活力、光合作用、抗氧化... 详细信息

微生物在修复重金属污染土壤中发挥重要作用。为阐明假单胞菌TCd-1降低水稻镉吸收的机理,通过加镉土培盆栽试验,在10 mg/kg镉处理下,对比研究了接种菌株对2种镉耐性不同水稻品种(特优671、百香139)镉含量、根系活力、光合作用、抗氧化酶活性及抗氧化物质含量的影响。结果表明:与10 mg/kg镉处理相比,接种假单胞菌TCd-1后水稻“特优671”和“百香139”的根、茎、叶、糙米的镉含量分别依次降低了30.4%、39.1%、40.7%、29.2%和52.2%、51.7%、18.4%、38.8%;提高了2种水稻的根系活力、光合作用,促进了水稻的生长;“特优671”、“百香139”叶片的超氧化物歧化酶(Superoxide dismutase,SOD)活性分别提高了7.3%、138.5%,过氧化物酶(Peroxidase,POD)活性提高了82.0%、106.2%,过氧化氢酶(Catalase,CAT)活性提高了58.8%、172.7%;叶片的类黄酮含量提高了139.4%、73.6%,总酚含量提高了27.2%、23.1%;超氧阴离子含量降低了44.2%、29.0%,丙二醛(Malondialdehyde,MDA)含量降低了38.5%、28.9%。因此,接种假单胞菌TCd-1提高了水稻抗氧化能力,减轻了氧化胁迫,促进了水稻的生长。

关键词：假单胞菌TCd-1 镉污染水稻生理特性

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Piezoelectric Nanogenerator Based on Electrospun Cellulose Acetate/Nanocellulose Crystal Composite Membranes for Energy Harvesting Application

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Chemical Research in Chinese Universities 2022年第4期38卷 1005-1011页

作者： SUN bolun CHAO Danming WANG Ce Alan G.MacDiarmid Institute Jilin UniversityChangchun130012P.R.China

Nanogenerators,as the typical conversion of mechanical energy to electrical energy devices,have great potential in the application of providing sustainable energy sources for powering miniature *** this work,cellulose acetate/cellulose nanocrystal(CA/CNC)composite nanofiber membranes were prepared by electrospinning method and then utilized to manufacture a flexible pressure-driven *** addition of CNC not only increased the content of piezoelectric cellulose I crystallization but also strengthened the mechanical deformation of the nanofiber membranes,which could greatly enhance the piezoelectric performance of CA/CNC composite *** CA/CNC composite nanofiber membrane with 20%(mass fraction)of CNC(CA/CNC-20%)showed optimal piezoelectric conversion performance with the output voltage of 1.2 V under the force of 5 N(frequency of 2 Hz).Furthermore,the output voltage of the CA/CNC-20%nanogenerator device exhibited a linear relationship with applied impact force,indicating the great potential in pressure sensors.

关键词： Piezoelectric Nanogenerator Electrospinning Cellulose acetate Nanocellulose crystal

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