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Influences of Multi-Component Supplementary Cementitious Materials on the Performance of Metakaolin Based Geopolymer

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Journal of renewable Materials 2022年第7期10卷 1813-1828页

作者： Wu Jing ren luo Sha Ding Ping Duan School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan430070China Wuhan Hanyang Municipal Construction Group Co. Ltd.Wuhan430050China Faculty of Materials Science and Chemistry Key Laboratory of Geological Survey and Evaluation of Ministry of EducationChina University of GeosciencesWuhan430074China Guangxi Key Laboratory of New Energy and Building Energy Saving Guilin University of TechnologyGuilin541004China Zhejiang Institute China University of Geosciences(Wuhan)Hangzhou311305China Key Laboratory of Advanced Building Materials of Anhui Province Anhui Jianzhu UniversityHefei230022China Key Laboratory of Road Structure and Materials of Ministry of Transport Chang’an UniversityXi’an710064China

In this study,the workability and reaction mechanism of metakaolin(MK)based geopolymer blended with rice husk ash(RHA)and silica fume(SF)was investigated.The prepared samples were subjected to tests including compressive strength and fluidity tests.X-ray diffraction(XRD)and Scanning electron microscope(SEM)were employed to explore the phase composition and microstructure of geopolymers.The molecular bonding information of geopolymer was provided by Fourier transform infrared spectroscopy(FTIR).Meanwhile,the porosity of geopolymer was obtained by Mercury intrusion porosimeter(MIP)analysis.The high-activity RHA obtained after calcination at 600℃ was used as a supplementary cementitious material to prepare geopolymer.The properties of preventing morphology cracking and compressive strength are improved.The addition of RHA and SF changes the working performance of MK based geopolymer and provided a theoretical basis for future practical applications.Meanwhile,the high chemical activity of SF and RHA contributes to the healing of microcracks.

关键词： Rice husk ash silica fume metakaolin geopolymer

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Reliable Ge_(2)Sb_(2)Te_(5) based phase-change electronic synapses using carbon doping and programmed pulses

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Journal of Materiomics 2022年第2期8卷 382-391页

作者： Qiang Wang Gang Niu Ruobing Wang ren luo Zuo-Guang Ye Jinshun Bi Xi Li Zhitang Song Wei ren Sannian Song Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education&International Center for Dielectric ResearchSchool of Electronic Science and EngineeringXi'an Jiaotong UniversityXi'an710049China State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and InformationTechnologyChinese Academy of Sciences865 Changning RoadShanghai200050China Department of Chemistry and 4D LABS Simon Fraser UniversityBurnabyBritish ColumbiaV5A 1S6Canada Key Laboratory of Microelectronics Device and Integrated Technology The Institute of Microelectronics of Chinese Academy of SciencesBeijing100029China University of Chinese Academy of Sciences Beijing100049China

Hardware electronic synapse and neuro-inspired computing system based on phase change random access memory(PCRAM)have attracted an extensive investigation.However,due to the intrinsic asymmetric reversible phase transition,the defective weight update of PCRAM synapses in aspects of tuning range,linearity and continuity has long required a system-level complexity of circuits and al-gorithms.The cell-level improvements to a great extent may slim the system thus achieving efficient computing.We report in this work the great enhancement of Ge_(2)Sb_(2)Te_(5)(GST)based PCRAM synapses by combining materials engineering and pulse programming.It is found that carbon doping in GST retards the rate of phase changing thus increasing the controllability of the conductance,while non-linear programmable pulse excitations can eventually lead to a reliable synaptic potentiation and depression.A set of improved programmable pulse schemes for spike-timing dependent plasticity was then demonstrated,suggesting its potential superiority in flexible programming and reliable data collection.Our methods and results are of great significance for implementing PCRAM electronic synapses and high-performance neuro-inspired computing.

关键词： Programmable synapse Synaptic simulation PCRAM C-doped Ge_(2)Sb_(2)Te_(5) Electronic synapse

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Improved lateral-dynamics-intended railway vehicle model involving nonlinear wheel/rail interaction and car body flexibility

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Acta Mechanica Sinica 2021年第6期37卷 997-1012,I0003页

作者： Huailong Shi ren luo Jinying Guo State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu610031China School of Automobile and Transportation Chengdu Technological UniversityChengdu611730China

To study the vehicle hunting behavior and its coupling with car body vibrations,a simplified lateral-dynamics-intended railway vehicle model is developed.A two-truck vehicle is modeled as a 17 degrees-of-freedom rigid system,into which the car body flexural vibrations of torsion and bending modes are further integrated.The wheel/rail interaction employs a real-time calculation for the Hertzian normal contact,in which the nonlinear curvatures of wheel and rail profiles are presented as functions of wheelset lateral movement and/or yaw rotation.Then the tangential/creep forces are analytically expressed as the Hertzian contact patch geometry,and lead to a continuous and fast calculation compared to a look-up table interpolation.It is shown that the hunting frequencies of the vehicle model and a truck model differ significantly,which verifies the necessity of the whole vehicle model.In the case of low wheel/rail conicity,the hunting frequency increases linearly with vehicle speed,whereas it rises slowly at high speed for a large conicity.Comparison of hunting frequency and damping ratio between various conicities shows that first hunting(car body hunting)may occur when the vehicle is operated at a low speed in a small conicity case,while a second hunting(truck hunting)appears when the vehicle is operated at a high speed in a large conicity case.Stability analysis of linear and nonlinear vehicle models was carried out through coast down method and constant speed simulations.Results tell that the linear one overestimates the lateral vibrating.Whereas the structural vibrations of car body can be ignored in the stability analysis.Compared to existing simplified models for hunting stability study,the proposed simplified vehicle model released limitations in the nonlinear geometries of wheel/rail profiles,and it is suitable for a frequency-domain analysis by deriving the analytical expressions of the normal and tangential wheel/rail contact forces.

关键词： Railroad vehicle Wheel/rail contact Analytical forms Hunting stability Car body flexibility

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高速列车空气弹簧二系悬挂垂向振动规律研究

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机械制造与自动化 2024年第2期53卷 214-219页

作者：张传阳罗仁中国铁路设计集团有限公司天津300308 西南交通大学牵引动力国家重点实验室四川成都610031

建立空气弹簧系统垂向非线性动力学模型和某高速列车动力学模型,根据空簧垂向振动传递试验结果,验证空簧非线性动力学模型的准确性,采用数值仿真分析空簧的垂向动刚度特性和振动传递规律。研究二系抗侧滚扭杆刚度、空簧节流孔直径和二... 详细信息

建立空气弹簧系统垂向非线性动力学模型和某高速列车动力学模型,根据空簧垂向振动传递试验结果,验证空簧非线性动力学模型的准确性,采用数值仿真分析空簧的垂向动刚度特性和振动传递规律。研究二系抗侧滚扭杆刚度、空簧节流孔直径和二系垂向减振器阻尼对振动传递规律的影响,对比不同二系悬挂结构对车辆动力学指标的影响,发现节流孔直径对空簧动刚度和传递率影响很大,减小节流孔直径会增大空簧垂向动刚度;采用节流孔方式有利于改善高频减振效果,采用二系垂向减振器有利于低频减振。研究结果表明:采用合适直径的节流孔可以实现和二系垂向减振器近似的振动传递率,且减小垂向平稳性指标值及车体垂向加速度值。

关键词：高速列车空气弹簧动力学仿真振动传递垂向减振器

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Influence of equipment excitation on flexible carbody vibration of EMU

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Journal of Modern Transportation 2014年第4期22卷 195-205页

作者： Huailong Shi ren luo Pingbo Wu Jing Zeng Jinying Guo State Key Laboratory of Traction Power Southwest Jiaotong University

To study the vibration transmission character istics of a flexible carbody and its suspended equipment, a vertical mathematical model of highspeed electric multiple unit was established with equipment excitation considered. And the dynamic unbalance and impact turbulence excita tion from equipment were taken into account in a single stage and twostage vibration isolation system, respectively. Results show that the excitation transferred to carbody increases with suspension stiffness but decreases with the equipment mass increasing; the vibration transmission can be reduced by increasing the equipment mass or reduce the suspension stiffness. To avoid vibration resonance, the dynamic unbalance frequency of equipment should be out of the possible range of the carbody flexible modes, and a small stiffness should be applied to reduce the impact tur bulence. A small stiffness, however, would result in a large movement of the equipment which is limited by the static deflection requirement, while a great stiffness will transfer high frequency vibration. Therefore, a preferred stiffness should make the suspension frequency of equipment a bit greater than the first bending mode of carbody. Additionally, a 3D rigidflexible coupled dynamics model was built to verify the mathematical analysis, and they show good agreements. Results show that a twostage isolation could reduce the excitation transmission and make the vibration of carbody and equipment acceptable.

关键词： Flexible carbody Suspended equipment Vibration transmission Dynamic unbalance Impact

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Cerebral proliferative angiopathy in pediatric age presenting as neurological disorders:A case report

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World Journal of Clinical Cases 2023年第33期11卷 8071-8077页

作者： Fu-ren luo Ying Zhou Zhong Wang Qi-Yu Liu Department of Radiology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Radiology Mianyang Central HospitalMianyang 621000Sichuan ProvinceChina

BACKGROUND Cerebral proliferative angiopathy(CPA)is a rare subtype of arteriovenous malformation.It is extremely rare in pediatric patients and has serious implications for developing children.However,reports of these disorders worldwide are limited,and no uniform reference for diagnosis and treatment options exists.We report the case of a 6-year-old with CPA having predominantly neurological dysfunction and review the literature on pediatric CPA.CASE SUMMARY We report the case of a pediatric patient with CPA analyzed using digital subtraction angiography(DSA)who presented initially with a neurological disorder as the main manifestation.This case is the basis for further discussion of the clinical presentation,pathogenesis,diagnosis,and treatment of CPA in children.After the cerebral DSA,the patient was treated conservatively with sedation,fluid replacement,and blood anticoagulation.She could not cooperate with the followup magnetic resonance imaging examination because of her young age,and her family declined further treatment because of the surgery’s high risk.She was followed up for 3 months;her symptoms did not worsen.CONCLUSION This report of rare pediatric CPA can inform and advance clinical research on congenital cerebrovascular diseases.

关键词： Pediatric cerebral proliferative angiopathy Pathogenesis Diagnosis Treatment Case report

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Elucidating the structure-activity relationship of Cu-Ag bimetallic catalysts for electrochemical CO_(2) reduction

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Journal of Energy Chemistry 2024年第6期93卷 345-351,I0009页

作者： Qining Huang Lili Wan Qingxuan ren Jingshan luo Institute of Photoelectronic Thin Film Devices and Technology State Key Laboratory of Photovoltaic Materials and CellsKey Laboratory of Photoelectronic Thin Film Devices and Technology of TianjinMinistry of Education Engineering Research Center of Thin Film Photoelectronic TechnologyNankai UniversityTianjin 300350China Frontiers Science Center for New Organic Matter Nankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Developing bimetallic catalysts is an effective strategy for enhancing the activity and selectivity of electrochemical CO_(2) reduction reactions,where understanding the structure-activity relationship is essential for catalyst design.Herein,we prepared two Cu-Ag bimetallic catalysts with Ag nanoparticles attached to the top or the bottom of Cu nanowires.When tested in a flow cell,the Cu-Ag catalyst with Ag nanoparticles on the bottom achieved a faradaic efficiency of 54%for ethylene production,much higher than the catalyst with Ag nanoparticles on the top.The catalysts were further studied in the H-cell and zero-gap MEA cell.It was found that placing the two metals in the intensified reaction zone is crucial to triggering the tandem reaction of bimetallic catalysts.Our work elucidates the structure-activity relationship of bimetallic catalysts for CO_(2) reduction and demonstrates the importance of considering both catalyst structures and cell characteristics to achieve high activity and selectivity.

关键词： Electrochemical CO_(2)reduction Bimetallic catalyst Cu-Ag Structure-activity relationship

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Maximizing conditional independence for unsupervised domain adaptation

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Science China(Information Sciences) 2024年第5期67卷 136-149页

作者： Yiming ZHAI Chuanxian ren Youwei luo Daoqing DAI School of Mathematics Sun Yat-Sen University

Unsupervised domain adaptation(UDA) studies how to transfer a learner from a labeled source domain to an unlabeled target domain with different distributions. Existing methods mainly focus on matching marginal distributions of the source and target domains, which probably leads to a misalignment of samples from the same class but different domains. In this paper, we tackle this misalignment issue by achieving the class-conditioned transferring from a new perspective. Specifically, we propose a method named maximizing conditional independence(MCI) for UDA, which maximizes the conditional independence of feature and domain given class in the reproducing kernel Hilbert spaces. The optimization of conditional independence can be viewed as a surrogate for minimizing class-wise mutual information between feature and domain. An interpretable empirical estimation of the conditional dependence measure is deduced and connected with the unconditional case. Besides, we provide an upper bound on the target error by taking the class-conditional distribution into account, which provides a new theoretical insight for class-conditioned transferring. Extensive experiments on six benchmark datasets and various ablation studies validate the effectiveness of the proposed model in dealing with UDA.

关键词： conditional independence kernel method domain adaptation class-conditioned transferring

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锂离子电池模组自适应均衡阀值控制策略研究

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机电产品开发与创新 2024年第1期37卷 107-110页

作者：姚琳娜罗仁宏刘瑛王之丰上海市工业技术学校上海200001 武汉商贸职业学院现代工业技术学院湖北武汉430000 中汽研汽车检验中心(常州)有限公司江苏常州230000 浙江省吉利汽车研究院有限公司浙江杭州315336

为提升锂离子电池模组均衡控制能力,提出一种锂离子电池模组自适应均衡阀值控制策略。首先,对电感式主动均衡电路拓扑和工作原理进行分析。接着,基于电感式主动均衡电路设计了自适应均衡阀值动态调整控制方法,利用电量转移矩阵计算最佳... 详细信息

为提升锂离子电池模组均衡控制能力,提出一种锂离子电池模组自适应均衡阀值控制策略。首先,对电感式主动均衡电路拓扑和工作原理进行分析。接着,基于电感式主动均衡电路设计了自适应均衡阀值动态调整控制方法,利用电量转移矩阵计算最佳转移路径。然后,搭建仿真计算模型,通过验证本控制策略能提高目标电池模组均衡能力。最后,对目标电池模组进行实验验证,验证了本控制策略的有效性和高效性,为电池模组均衡提供方法参考。

关键词：锂离子电池模组自适应均衡阀值均衡控制策略电感式

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Yemazhui(Herba Eupatorii Lindleyani)ameliorates lipopolysaccharide-induced acute lung injury via modulation of the toll-like receptor 4/nuclear factor kappa-B/nod-like receptor family pyrin domain-containing 3 protein signaling pathway and intestinal flor

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Journal of Traditional Chinese Medicine 2024年第2期44卷 303-314页

作者： ren Li HAI Yang YANG Xue luo Xianqin Chongqing Key Laboratory of Traditional Chinese Medicine for Prevention and Cure of Metabolic Diseases College of Traditional Chinese MedicineChongqing Medical UniversityChongqing 400016China College of Basic Medicine Chongqing Medical UniversityChongqing 400016China

OBJECTIVE:To investigate the impact of Yemazhui(Herba Eupatorii Lindleyani,HEL)against lipopolysaccharide(LPS)-induced acute lung injury(ALI)and explore its underlying mechanism in vivo.METHODS:The chemical constituents of HEL were analyzed by ultra-high performance liquid chromatographyquadrupole time-of-flight mass spectrometry method.Then,HEL was found to suppress LPS-induced ALI in vivo.Six-week-old male Sprague-Dawley rats were randomly divided into 6 groups:control,LPS,Dexamethasone(Dex),HEL low dose 6 g/kg(HEL-L),HEL medium dose 18 g/kg(HEL-M)and HEL high dose 54 g/kg(HEL-H)groups.The model rats were intratracheally injected with 3 mg/kg LPS to establish an ALI model.Leukocyte counts,lung wet/dry weight ratio,as well as myeloperoxidase(MPO)activity were determined followed by the detection with hematoxylin and eosin staining,enzyme linked immunosorbent assay,quantitative real time polymerase chain reaction,western blotting,immunohistochemistry,and immunofluorescence.Besides,to explore the effect of HEL on ALI-mediated intestinal flora,we performed 16s rRNA sequencing analysis of intestinal contents.RESULTS:HEL attenuated LPS-induced inflammation in lung tissue and intestinal flora disturbance.Mechanism study indicated that HEL suppressed the lung coefficient and wet/dry weight ratio of LPS-induced ALI in rats,inhibited leukocytes exudation and MPO activity,and improved the pathological injury of lung tissue.In addition,HEL reduced the expression of tumor necrosis factoralpha,interleukin-1beta(IL-1β)and interleukin-6(IL-6)in bronchoalveolar lavage fluid and serum,and inhibited nuclear displacement of nuclear factor kappa-B p65(NF-κBp65).And 18 g/kg HEL also reduced the expression levels of toll-like receptor 4(TLR4),myeloid differentiation factor 88,NF-κBp65,phosphorylated inhibitor kappa B alpha(phospho-IκBα),nod-like receptor family pyrin domain-containing 3 protein(NLRP3),IL-1β,and interleukin-18(IL-18)in lung tissue,and regulated intestinal flora disturbance.CONCLUSIONS:In summary,our findings revealed

关键词： Yemazhui(Herba Eupatorii Lindleyani) acute lung injury anti-inflammation toll-like receptor 4 nuclear factor kappa-B nod-like receptor family pyrin domain-containing 3 protein signal transduction gastrointestinal microbiome

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