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Safety threshold of high-speed railway pier settlement based on train-track-bridge dynamic interaction

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Science China(Technological Sciences) 2015年第2期58卷 202-210页

作者： CHEN Zhao wei ZHAI Wan Ming CAI Cheng Biao SUN yu State Key Laboratory of Traction Power Southwest Jiaotong University

This paper presents a method to determine the safety threshold of bridge pier settlement in high-speed *** analytical expression of the mapping relationship between the pier settlement and the rail deformation is derived theoretically for the double block ballastless track-bridge *** adopting the superposition of the track random irregularity and the rail deformation caused by the pier settlement as the excitation inputs,the variations of vehicle dynamics indices with pier settlement are comparatively ***,the safety threshold of the bridge pier settlement is obtained according to the limit of vehicle running safety and ride comfort indices of the high-speed *** show that the dynamics indices of different trains have different sensitivities to the pier settlement,and the train CRH2C is the most sensitive one among all the types of Chinese high-speed *** passing through the bridges in common span with pier settlement at the speed of 250–350 km/h,the trains suffer the low-frequency excitations,and the vertical acceleration of car body is most sensitive to the pier settlement of all the dynamics *** the car body vertical acceleration just exceeds the allowable limit,the critical settlement value is 23.4 mm,which is much bigger than the pier differential settlement limit in the current code for Chinese high-speed railways.

关键词： high-speed railway pier settlement safety threshold dynamic characteristics train-track-bridge dynamic interaction

1.9 Ga eclogite from the Archean-Paleoproterozoic Belomorian Province, Russia

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Science Bulletin 2017年第4期62卷 239-241页

作者： Xiaoli Li Huanglu yu Lifei Zhang Chunjing wei Thomas Bader The Key Laboratory of Orogenic Belts and Crustal Evolution MOE School of Earth and Space Sciences Peking University Beijing 100871 China

The first Archean eclogite was announced from the Salma and Gridino complexes of Belomorian Province(Russia)in Fennoscandian Shield(Fig.1a)[1]that has aroused quite a resonance worldwide from all aspects;the debates on the actual age of the Belomorian eclogites have never stopped ever since and in all there are three scenarios are suggested(1)one time in Mesoarchean,(2)two times in Neoarchean and Paleoproterozoic and(3)one time

关键词：古元古代榴辉岩太古宙俄罗斯 GA 世界范围新太古代

Microstructure-based finite element modeling of effect of metastable austenite on mechanical properties of quenching and partitioning (Q&P)980 steel

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Journal of Iron and Steel Research International 2018年第11期25卷 1140-1148页

作者： Hui Zheng wei Li yu Gong Li Wang Xue-jun Jin Institute of Advanced Steels and Materials School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai Jiao Tong University Shanghai 200240China State Key Lab of Development and Application Technology of Automotive Steels Baosteel Research Institute Shanghai 201900China

The microstructure-based finite element modeling was conducted to study the mechanical properties of Q&P 980 steel at the microscopic *** two-dimensional representative volume elements of real microstructure were obtained from electron backscattered diffraction ***-Kocks equation was used to predict the constitutive strain-stress relationships of individual ***-induced martensitic transformation takes place when the driving force exceeds the critical driving force according to a stress-invariant-based *** macroscopic stress-strain curves and the work-hardening rate curves obtained from modeling fit well with the experimental *** simulation results also indicate that the local distributions of stress and strain in constituent phases are dependent on their *** ferrite carries the highest strain,while hard mechanical-induced martensite carries the highest *** comparing the modeling results of the microstructures with and without austenite,it shows that the transformation of retained austenite to hard martensite can increase the .work-hardening ability and hence improve the strength and ductility of the *** detailed finite element modeling methods and results are presented and discussed.

关键词： Q&P steel Retained austenite Mechanical property TRIP effect Finite element modeling

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汉麻纤维纸的抄造工艺及其性能研究

齐齐哈尔大学学报（自然科学版） 2024年第2期40卷 80-83页

作者：唐银李梓萌史长伟孙尚冯森高青云朱思渝郑永杰齐齐哈尔大学轻工与纺织学院黑龙江齐齐哈尔161006 齐齐哈尔大学化学与化学工程学院黑龙江齐齐哈尔161006 寒区麻及其制品教育部工程研究中心黑龙江齐齐哈尔161006

利用汉麻落麻纤维为原料进行打浆,配合漂白针叶木浆抄造出一系列汉麻纤维纸,并对物理性能进行了测定。对打浆的工艺条件进行了分析,由于汉麻落麻纤维直径小,打浆过程容易产生细小纤维,使得打浆度升高但部分长纤维难以切断。以不同比例... 详细信息

利用汉麻落麻纤维为原料进行打浆,配合漂白针叶木浆抄造出一系列汉麻纤维纸,并对物理性能进行了测定。对打浆的工艺条件进行了分析,由于汉麻落麻纤维直径小,打浆过程容易产生细小纤维,使得打浆度升高但部分长纤维难以切断。以不同比例配合制备了汉麻纤维和漂白针叶木浆复合浆纸,考察了不同的配比和定量对纸张性能的影响。汉麻浆绝干浆质量分数为30%,纸张的抗张性能最佳,汉麻浆的质量分数与耐折度正相关。定量越大,纸张的物理性能均有所提升。经过处理汉麻纤维的分丝帚化良好,汉麻细小纤维和漂白针叶木纤维充分交织促进了纤维之间的结合。

关键词：汉麻落麻打浆度抗张性能耐折度

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敲低CCAAT/增强子结合蛋白β促进肝癌细胞的增殖和迁移

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中国生物化学与分子生物学报 2024年第6期40卷 797-806页

作者：陈利荣刘玉玲贾艳梅梁紫微李佳佳山西医科大学汾阳学院医学检验系山西汾阳032200 太原理工大学生物医学工程学院太原030000 山西医科大学研究生学院太原030000

近年来已有研究表明,C/EBPβ在肝癌的发生发展中发挥重要的作用,但其具体分子调控机制尚不清楚。本研究通过分析GEO数据库和Kaplan-Meier Plotter数据库发现,C/EBPβmRNA在肝癌中低表达(P<0.05),且其低表达与肝癌患者预后密切相关。进一... 详细信息

近年来已有研究表明,C/EBPβ在肝癌的发生发展中发挥重要的作用,但其具体分子调控机制尚不清楚。本研究通过分析GEO数据库和Kaplan-Meier Plotter数据库发现,C/EBPβmRNA在肝癌中低表达(P<0.05),且其低表达与肝癌患者预后密切相关。进一步,通过功能富集分析和TIMER数据库分析显示,C/EBPβ主要参与细胞周期、DNA转录等生物学过程,且C/EBPβ表达水平与CD4^(+)T细胞和巨噬细胞的免疫浸润具有较强的相关性(P<0.05)。为了进一步研究C/EBPβ对肝癌细胞增殖和迁移的影响。在肝癌细胞中瞬时转染C/EBPβsiRNA,将其分为si-NC组和siC/EBPβ组。通过qRT-PCR、Western印迹检测肝癌细胞中C/EBPβ在mRNA和蛋白质水平均显著降低(P<0.05);通过MTT检测、平板克隆形成实验和5-乙炔基-2-脱氧尿嘧啶核苷(Edu)实验证实,敲低C/EBPβ促进肝癌细胞的增殖(P<0.05);Transwell和划痕实验证实,敲低C/EBPβ促进肝癌细胞的迁移;Western印迹法检测敲低C/EBPβ对肝癌细胞内迁移相关蛋白质(E-cadherin、N-cadherin)以及Wnt/β-catenin信号通路蛋白质表达的影响,结果表明,敲低C/EBPβ促进肝癌细胞EMT上皮间质转化,并能激活Wnt/β-catenin信号通路的基因表达(P<0.05)。综上所述,C/EBPβ在肝癌组织中低表达且与患者生存预后成正相关。敲低C/EBPβ可能通过激活Wnt/β-catenin信号通络促进肝癌细胞的增殖、迁移和上皮间质转化,为C/EBPβ在肝癌的发生发展中的作用提供了依据,可能是一个肝癌诊治过程中的潜在靶点。

关键词：肝癌细胞增殖细胞迁移 CCAAT/增强子结合蛋白β

Uranyl photocatalysis:precisely controlled oxidation of sulfides with ground-state oxygen

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Science China Chemistry 2020年第3期63卷 291-293页

作者： wei-Min He Ying-Wu Lin Dong-Hong yu Department of Chemistry Hunan University of Science and EngineeringYongzhou 425100China Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation Changsha University of Science and TechnologyChangsha 410114China School of Chemistry and Chemical Engineering University of South ChinaHengyang 421001China Department of Chemistry and Bioscience Aalborg UniversityDK-9220 AalborgEastDenmark

Sulfur-containing organic compounds such as sulfides,sulfoxides and sulfones,have played significant roles in the fields of organic synthesis,pharmaceuticals,and *** selective oxidation of the parent sulfides has been... 详细信息

关键词： Uranyl oxidation ground-state oxygen

Structural Design and Application of Azo-based Supramolecular Polymer Systems

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Chinese Journal of Polymer Science 2019年第12期37卷 1183-1199,I0004页

作者： Hui-Tao yua Jun-Wen Tang Yi-yu Feng wei Feng School of Materials Science and Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Advanced Ceramics and Machining Technology Ministry of EducationTianjin 300072China Tianjin Key Laboratory of Composite and Functional Materials Tianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072China

This article presents a brief overview of recent advances in azo-containing supramolecular *** literature,it has been shown that azo supramolecular polymers and their composite materials exhibit fast and intelligent responses to various external stimuli,such as temperature,pH change,redox reagents,ligands,coupling reagents,*** applications,these systems are widely used for molecular motors,shape memory,liquid crystal,solar thermal energy storage,signal transmission,intelligent encryption,and other ***,these systems can function as key components for device upgrade ***,the design and rules of azo supramolecular polymers are still not supported by an exact *** about the relationship between the spatial structure and behavior is lacking,and new supramolecular materials cannot be designed by adding functional moieties to known azo *** on the current research status,this review mainly summarizes the structural design principles as well as structures and applications of known azo supramolecules;meanwhile,it highlights the emerging development fields,recent advances,and prospects in fabricating sei住assembling intelligent supramolecular systems with azo supramolecular polymers as responsive *** goal of this review is to bring new inspiration to researchers who want to optimize the chemical structure,steric conformation,electrostatic environment,and specific molecular functionalization.

关键词： Azo Supramolecular Structures Application Prospect

Development of a database system for operational use in the selection of titanium alloys

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International Journal of Minerals,Metallurgy and Materials 2011年第4期18卷 444-449页

作者： yuan-fei Han wei-dong Zeng yu Sun Yong-qing Zhao State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi＇an 710072 China Northwest Institute for Nonferrous Metal Research Xi＇an 710016 China

The selection of titanium alloys has become a complex decision-making task due to the growing number of creation and utilization for titanium alloys,with each having its own characteristics,advantages,and *** choosing the most appropriate titanium alloys,it is very essential to offer a reasonable and intelligent service for technical *** possible solution of this problem is to develop a database system（DS） to help retrieve rational proposals from different databases and information sources and analyze them to provide useful and explicit *** this purpose,a design strategy of the fuzzy set theory is proposed,and a distributed database system is *** ranking of the candidate titanium alloys,the most suitable material is *** is found that the selection results are in good agreement with the practical situation.

关键词： titanium alloys database system fuzzy set theory evaluation

食管癌术后肺部感染病原学和TNF基因微卫星多态性及TGF-β1/Smads信号通路表达

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中华医院感染学杂志 2024年第18期34卷 2757-2761页

作者：王志芳高薇张宁陈雨桐徐柯楠衡水市人民医院胸外科河北衡水053000

目的探讨食管癌(EC)患者术后肺部感染血浆肿瘤坏死因子(TNF)基因微卫星多态性、转化生长因子-β1(TGF-β1)/Smads信号通路蛋白水平变化及其病原学特点。方法选取2020年8月-2023年7月衡水市人民医院收治的60例EC术后发生肺部感染患者(感... 详细信息

目的探讨食管癌(EC)患者术后肺部感染血浆肿瘤坏死因子(TNF)基因微卫星多态性、转化生长因子-β1(TGF-β1)/Smads信号通路蛋白水平变化及其病原学特点。方法选取2020年8月-2023年7月衡水市人民医院收治的60例EC术后发生肺部感染患者(感染组)和70例EC术后未发生肺部感染患者(未感染组)。收集EC患者的临床资料并分析病原学特点,分析患者血浆TNF基因微卫星多态性,比较两组患者外周血TGF-β1、Smad2、Smad3、Smad7蛋白水平表达,分析TGF-β1、Smad2、Smad3、Smad7单独及联合检测对EC患者术后肺部感染的诊断价值。结果感染组60例EC患者共培养出61株病原菌,其中革兰阴性菌(67.21%)中的肺炎克雷伯菌、铜绿假单胞菌与革兰阳性菌(26.23%)中的金黄色葡萄球菌占比较高,真菌(6.56%)占比较少;与未感染组相比,感染组血浆中TNF基因微卫星分型TNFc 1/1基因型、TNFc1等位基因占比较高(P<0.05);与未感染组相比,感染组外周血TGF-β1、Smad2、Smad3和Smad7蛋白水平升高(P<0.05);TGF-β1、Smad2、Smad3和Smad7联合检测对EC患者术后肺部感染的诊断曲线下面积(AUC)值高于单独检测的AUC值(P<0.05),联合检测的特异度为87.14%,敏感度为86.67%。结论EC患者术后肺部感染病原菌主要为革兰阴性菌中的肺炎克雷伯菌、铜绿假单胞菌及革兰阳性菌中的金黄色葡萄球菌。EC患者术后肺部感染与血浆中TNF基因微卫星分型TNFc1/1基因型、TNFc1等位基因占比及TGF-β1/Smads信号通路蛋白水平变化有关,TGF-β1、Smad2、Smad3和Smad7联合检测对EC患者术后肺部感染具有较高的诊断价值。

关键词：食管癌肺部感染多态性肿瘤坏死因子转化生长因子-β1/Smads通路病原菌

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