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Particles attrition of binary mixtures in the coal-fueled chemical looping system based on fluidized bed

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Particuology 2024年第3期86卷 281-290页

作者： Heyu Li Zhe Sun Yan cao Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China University of Chinese Academy of Sciences Bejing 100049China CAS Key Laboratory of Renewable Energy Guangzhou 510640China Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640China College of Chemistry and Chemical Engineering Anhui UniversityHefei230601China

In this work,a reactive air jet attrition device with auto-recording and collection of elutriated fines was developed.Results established insights into the physiochemical interaction and further correlated attrition behaviors between char and oxygen carriers under various operation modes.The attrition rate increased by over 110% upon the introduced CO_(2),which brought in the significant effect of thermo-chemical stress,similarly in effects of the increased char addition ratio and the decreased sizes of char or hematite in different extents.For the char-hematite co-attrition process,the elutriated carbon loss of char with poor mechanical strength was found to be over 10%,while the reactive iron loss of hematite was found to be 6.3%,and was enriched in elutriated fines.The reaction-derived thermochemical stress and the collision-derived mechanical stress jointly controls the particle attrition during the cyclic transformation of oxygen carrier particles in coal-fueled chemical looping fluidization,especially sig-nificant in its reduction stage.

关键词： Attrition Binary species Chemical looping Oxygen carrier CO_(2)capture

Reinforcing effects of polypropylene on energy absorption and fracturing of cement-based tailings backfill under impact loading

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 650-664页

作者： Jiajian Li Shuai cao Erol Yilmaz School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of High-Efficient Mining and Safety of Metal Mines of Ministry of Education University of Science and Technology BeijingBeijing 100083China Department of Civil Engineering Geotechnical DivisionRecep Tayyip Erdogan UniversityFenerRize TR53100Turkey

Polypropylene(PP)fiber-reinforced cement-based tailings backfill(FRCTB)is a green compound material with superior crack resistance and has good prospects for application in underground mining.However,FRCTB exhibits susceptibility to dynamic events,such as impact ground pressure and blast vibrations.This paper investigates the energy and crack distribution behavior of FRCTB under dynamic impact,considering the height/diameter(H/D)effect.Split Hopkinson pressure bar,industrial computed tomography scan,and scanning electron microscopy(SEM)experiments were carried out on six types of FRCTB.Laboratory outcomes confirmed fiber aggregation at the bottom of specimens.When H/D was less than 0.8,the proportion of PP fibers distributed along theθangle direction of80°-90°increased.For the total energy,all samples presented similar energy absorption,reflectance,and transmittance.However,a rise in H/D may cause a rise in the energy absorption rate of FRCTB during the peak phase.A positive correlation existed between the average strain rate and absorbed energy per unit volume.The increase in H/D resulted in a decreased crack volume fraction of FRCTB.When the H/D was greater than or equal to 0.7,the maximum crack volume fraction of FRCTB was observed close to the incidence plane.Radial cracks were present only in the FRCTB with an H/D ratio of 0.5.Samples with H/D ratios of 0.5 and 0.6 showed similar distributions of weakly and heavily damaged areas.PP fibers can limit the emergence and expansion of cracks by influencing their path.SEM observations revealed considerable differences in the bonding strengths between fibers and the FRCTB.Fibers that adhered particularly well to the substrate were attracted together with the hydration products adhering to surfaces.These results show that FRCTB is promising as a sustainable and green backfill for determining the design properties of mining with backfill.

关键词： cement-based tailings fiber-reinforced backfills fracture energy absorption impact loading

Exploring the influences of education,intelligence and income on mental disorders

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General Psychiatry 2024年第1期37卷 64-72页

作者： Ancha Baranova Hongbao cao Fuquan Zhan George Mason University FairfaxVirginiaUSA Research Centre for Medical Genetics MoscowRussia nanjing Medical University Affiliated Brain Hospital NanjingZhejiangChina

Background Previous studies have shown that educational attainment(EA),intelligence and income are key factors associated with mental disorders.However,the direct effects of each factor on major mental disorders are unclear.Aims We aimed to evaluate the overall and independent causal effects of the three psychosocial factors on common mental disorders.Methods Using genome-wide association study summary datasets,we performed Mendelian randomisation(MR)and multivariable MR(MVMR)analyses to assess potential associations between the 3 factors(EA,N=766345;household income,N=392422;intelligence,N=146808)and 13 common mental disorders,with sample sizes ranging from 9907 to 807553.Inverse-variance weighting was employed as the main method in the MR analysis.Results Our MR analysis showed that(1)higher EA was a protective factor for eight mental disorders but contributed to anorexia nervosa,obsessive-compulsive disorder(OCD),bipolar disorder(BD)and autism spectrum disorder(ASD);(2)higher intelligence was a protective factor for five mental disorders but a risk factor for OCD and ASD;(3)higher household income protected against 10 mental disorders but confers risk for anorexia nervosa.Our MVMR analysis showed that(1)higher EA was a direct protective factor for attention-deficit/hyperactivity disorder(ADHD)and insomnia but a direct risk factor for schizophrenia,BD and ASD;(2)higher intelligence was a direct protective factor for schizophrenia but a direct risk factor for major depressive disorder(MDD)and ASD;(3)higher income was a direct protective factor for seven mental disorders,including schizophrenia,BD,MDD,ASD,post-traumatic stress disorder,ADHD and anxiety disorder.Conclusions Our study reveals that education,intelligence and income intertwine with each other.For each factor,its independent effects on mental disorders present a more complex picture than its overall effects.

关键词： protective disorders income

The Method of Polynomial Particular Solutions for Solving Nonlinear Poisson-Type Equations

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Acta Mechanica Solida Sinica 2024年第1期37卷 155-165页

作者： Zhile Jia Yanhua cao Xiaoran Wu School of Sciences East China Jiaotong UniversityNanchang 330013China

In this paper,the method of polynomial particular solutions is used to solve nonlinear Poisson-type partial differential equations in one,two,and three dimensions.The condition number of the coefficient matrix is reduced through the implementation of multiple scale technique,ultimately yielding a stable numerical solution.The methodological process can be divided into two main parts:first,identifying the corresponding polynomial particular solutions for the linear differential operator terms in the governing equations,and second,employing these polynomial particular solutions as basis function to iteratively solve the remaining nonlinear terms within the governing equations.Additionally,we investigate the potential improvement in numerical accuracy for equations with singularities in the analytical solution by shifting the computational domain a certain distance.Numerical experiments are conducted to assess both the accuracy and stability of the proposed method.A comparison of the obtained results with those produced by other numerical methods demonstrates the accuracy,stability,and efficiency of the proposed method in handling nonlinear Poisson-type partial differential equations.

关键词： Nonlinear equation Singularity Polynomial particular solutions Poisson type

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汉语二语学习者主语回指语显隐的多因素分析

语言教学与研究 2024年第2期 24-34页

作者：曹娜曹贤文南京大学文学院 210023 南京大学海外教育学院/中国语言战略研究中心 210093

本文依托全球汉语中介语语料库,采用多因素分析方法考察了初、中、高级汉语二语学习者使用主语回指语的显隐现象。分析结果显示:除了汉语水平对二语学习者主语回指语的显隐具有显著影响以外,字符间隔距离、句式平行性、先行词句法位置... 详细信息

本文依托全球汉语中介语语料库,采用多因素分析方法考察了初、中、高级汉语二语学习者使用主语回指语的显隐现象。分析结果显示:除了汉语水平对二语学习者主语回指语的显隐具有显著影响以外,字符间隔距离、句式平行性、先行词句法位置、指称生命度、名词短语间隔距离、回指距离(句子)、回指距离(小句)等因素也对二语学习者主语回指语显隐具有显著影响,且这七个因素的影响权重不同,不过回指距离(段落)与关联词两个因素对主语回指语的显隐没有显著影响。

关键词：主语回指语显隐多因素分析中介语语料库汉语水平

星载微波部件微放电阈值的改进多粒子蒙特卡罗计算方法

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高电压技术 2024年第4期50卷 1752-1759页

作者：张娜曹猛王瑞白春江崔万照中国空间技术研究院西安分院空间微波通信全国重点实验室西安710100 西安交通大学电信学部电子科学与工程学院电子物理与器件教育部重点实验室西安710049

星载微波部件的微放电效应是导致航天器谐振类设备失谐、噪声电平抬高、输出功率下降,甚至影响通信信道乃至整个微波传输系统彻底失效的瓶颈问题之一。在设计阶段对星载微波部件微放电效应进行精准的评估是减少地面反复试验,避免延误研... 详细信息

星载微波部件的微放电效应是导致航天器谐振类设备失谐、噪声电平抬高、输出功率下降,甚至影响通信信道乃至整个微波传输系统彻底失效的瓶颈问题之一。在设计阶段对星载微波部件微放电效应进行精准的评估是减少地面反复试验,避免延误研制周期的重要手段。为了进一步改善现有蒙特卡洛方法的计算准确度问题,文中提出了一种精度更高的计算星载微波部件微放电阈值的蒙特卡罗方法,该方法对参与微放电过程的初始电子进行了动态调整,采用四阶龙格-库塔法推进微波部件中电子的运动轨迹,基于Furman模型描述电子与微波表面相互作用的二次电子发射过程,按照碰撞电子产生的实际二次电子个数及对应能量参与碰撞时刻后的微放电过程,该多粒子-多碰撞过程更加客观、准确地表征了微放电效应发生的物理过程。以平板传输线和同轴传输线为例,文中所提出的方法相对于已有的蒙特卡罗方法计算精度显著提升,同时计算效率优于商用CST的粒子模拟结果。

关键词：微放电二次电子发射蒙特卡罗方法阈值微波部件

Effect of Active–Passive Deformation on the Thrust by the Pectoral Fins of Bionic Manta Robot

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Journal of Bionic Engineering 2024年第2期21卷 718-728页

作者： Yang Lu Shaomin Meng Cheng Xing Yiwei Hao Yonghui cao Guang Pan Yong cao School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an710072China Unmanned Vehicle Innovation Center Ningbo Institute of NPUNingbo315103China State Key Lab of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou310027China Zhejiang Key Laboratory of Advanced Manufacturing Technology School of Mechanical EngineeringZhejiang UniversityHangzhou310027China

Bionic manta underwater vehicles will play an essential role in future oceans and can perform tasks,such as long-duration reconnaissance and exploration,due to their efficient propulsion.The manta wings’deformation is evident during the swimming process.To improve the propulsion performance of the unmanned submersible,the study of the deformation into the bionic pectoral fin is necessary.In this research,we designed and fabricated a flexible bionic pectoral fin,which is based on the Fin Ray®effect with active and passive deformation(APD)capability.The APD fin was actively controlled by two servo motors and could be passively deformed to variable degrees.The APD fin was moved at 0.5 Hz beat frequency,and the propulsive performance was experimentally verified of the bionic pectoral fins equipped with different extents of deformation.These results showed that the pectoral fin with active–passive deformed capabilities could achieve similar natural biological deformation in the wingspan direction.The average thrust(T)under the optimal wingspan deformation is 61.5%higher than the traditional passive deformed pectoral fins.The obtained results shed light on the design and optimization of the bionic pectoral fins to improve the propulsive performance of unmanned underwater vehicles(UUV).

关键词： Manta ray Bionic pectoral fin Fin Ray®effect Active-passive deformation(APD)

Applications of genetic code expansion technology in eukaryotes

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Protein & Cell 2024年第5期15卷 331-363页

作者： Qiao-ru Guo Yu J.cao State Key Laboratory of Chemical Oncogenomic Guangdong Provincial Key Laboratory of Chemical GenomicsPeking University Shenzhen Graduate SchoolShenzhen 518055China Institute of Chemical Biology Shenzhen Bay LaboratoryShenzhen 518132China

Unnatural amino acids(UAAs)have gained significant attention in protein engineering and drug development owing to their ability to introduce new chemical functionalities to proteins.In eukaryotes,genetic code expansion(GCE)enables the incorporation of UAAs and facilitates posttranscriptional modification(PTM),which is not feasible in prokaryotic systems.GCE is also a powerful tool for cell or animal imaging,the monitoring of protein interactions in target cells,drug development,and switch regulation.Therefore,there is keen interest in utilizing GCE in eukaryotic systems.This review provides an overview of the application of GCE in eukaryotic systems and discusses current challenges that need to be addressed.

关键词： genetic code expansion unnatural amino acid eukaryotes basic research therapeutic applications

Adsorption limitation investigation on olefins for Cu–BTC

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Friction 2024年第4期12卷 606-617页

作者： Xiao YANG Yunbo WANG Weihua cao ruizheng JIANG Guoxin XIE Yuying cao Xiaowen QI School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China Key Laboratory of Self-Lubricating Spherical Plain Bearing Technology of Hebei Province Yanshan UniversityQinhuangdao 066004China State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Aviation Key Laboratory of Science and Technology on Generic Technology of Self-Lubricating Spherical Plain Bearing Yanshan UniversityQinhuangdao 066004China

To utilize Cu-benzene-1,3,5-tricarboxylate(Cu-BTC)adsorbed lubricant oils in the self-lubricating field,the adsorption properties of Cu-BTC on different 1-olefins must be clarified.In this work,1-hexene,1-octene,1-nonene,1-decene,1-undecene,and 1-dodecene were studied by the Monte Carlo method and experimentally.The adsorption limit of Cu-BTC for n-olefins was determined as 1-undecene by the adsorption isotherms.This suggested a limit for even straight-chain molecules to the adsorption of Cu-BTC.The maximum ratio of the olefin length of the largest pore diameter(L/D)of Cu-BTC was approximately 1.57.Furthermore,theoretical calculations(radial distribution function(RDF))and experiments(infrared(IR)spectra)confirmed the interaction of n-olefin adsorbates and the Cu-BTC framework occurred between the-CH=of olefins and the Cu and O atoms of the Cu-BTC framework.This work adds to the understanding and investigation of the adsorption of liquid lubricants using Cu-BTC as a metal-organic framework(MOF).

关键词： metal-organic framework(MOF) Cu-benzene-1,3,5-tricarboxylate(Cu-BTC) Monte Carlo method adsorption properties 1-olefins