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Control measures for thermal effects during placement of span-scale girder segments on continuous steel box girder bridges

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2020年第4期21卷 255-267页

作者： Jin-feng WANG Jiang-tao ZHANG Zhong-xuan YANG Rong-qiao XU Department of Civil Engineering Zhejiang UniversityHangzhou 310058China

In this study, we examined the thermal effects throughout the process of the placement of span-scale girder segments on a 6×110-m continuous steel box girder in the Hong Kong-Zhuhai-Macao Bridge. Firstly, when a span-scale girder segment is temporarily stored in the open air, temperature gradients will significantly increase the maximum reaction force on temporary supports and cause local buckling at the bottom of the girder segment. Secondly, due to the temperature difference of the girder segments before and after girth-welding, some residual thermal deflections will appear on the girder segments because the boundary conditions of the structure are changed by the girth-welding. Thirdly, the thermal expansion and thermal bending of girder segments will cause movement and rotation of bearings, which must be considered in setting bearings. We propose control measures for these problems based on finite element method simulation with field-measured temperatures. The local buckling during open-air storage can be avoided by reasonably determining the appropriate positions of temporary supports using analysis of overall and local stresses. The residual thermal deflections can be overcome by performing girth-welding during a period when the vertical temperature difference of the girder is within 1 °C, such as after 22:00. Some formulas are proposed to determine the pre-set distances for bearings, in which the movement and rotation of the bearings due to dead loads and thermal loads are considered. Finally, the feasibility of these control measures in the placement of span-scale girder segments on a real continuous girder was verified: no local buckling was observed during open-air storage;the residual thermal deflections after girth-welding were controlled within 5 mm and the residual pre-set distances of bearings when the whole continuous girder reached its design state were controlled within 20 mm.

关键词： Steel box girder Span-scale girder segments Construction process Thermal effects Control measures

TDW5000E超高频脉冲方波氩弧焊机的研制

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电焊机 2014年第5期44卷 33-38页

作者：丁强华胜李力齐铂金杨舟杨明轩北京时代科技股份有限公司北京100085 北京航空航天大学北京100191

TDW 5000E超高频脉冲方波氩弧焊机采用超高频脉冲GTAW技术、新型IGBT拓扑电路以MCU数字化控制方案,实现了超快速电流上升/下降沿变化速率（di/dt≥50 A/μs）及0～ 100 kHz脉冲频率的达百安培的方波电流输出.与常规焊机相比,利用超高频... 详细信息

TDW 5000E超高频脉冲方波氩弧焊机采用超高频脉冲GTAW技术、新型IGBT拓扑电路以MCU数字化控制方案,实现了超快速电流上升/下降沿变化速率（di/dt≥50 A/μs）及0～ 100 kHz脉冲频率的达百安培的方波电流输出.与常规焊机相比,利用超高频脉冲GTAW技术的焊机在普通方波的基础上叠加超高频脉冲电流,其脉冲电流幅值、占空比、脉冲频率等参数均可独立调节,确保不同焊接工艺过程的精确控制.研究表明,在铝合金、钛合金等航空航天高强材料的焊接加工中,该技术可有效降低焊缝的气孔敏感性、细化晶粒,显著提高焊接接头力学性能,具有重要的工程应用价值.

关键词：超高频脉冲GTAW技术数字化控制航空航天高强材料力学性能

From bibliometric analysis: 3D printing design strategies and battery applications with a focus on zinc‐ion batteries

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SmartMat 2024年第1期5卷 59-82页

作者： xuan Gao Kejiang Liu Chang Su Wei Zhang Yuhang Dai Ivan P.Parkin Claire J.Carmalt Guanjie He Christopher Ingold Laboratory Department of ChemistryUniversity College LondonLondonUK Electrochemical Innovation Lab(EIL) Department of Chemical EngineeringUniversity College LondonLondonUK Department of Physics Hong Kong Baptist UniversityHong KongChina Nanyang Technopreneurship Center Nanyang Technological UniversitySingaporeSingapore

Three‐dimensional(3D)printing has the potential to revolutionize the way energy storage devices are designed and *** this paper,we explore the use of 3D printing in the design and production of energy storage devices,especially zinc‐ion batteries(ZIBs)and examine its potential advantages over traditional manufacturing methods.3D printing could significantly improve the customization of ZIBs,making it a promising strategy for the future of energy *** particular,3D printing allows for the creation of complex,customized geometries,and designs that can optimize the energy density,power density,and overall performance of ***,we discuss and compare the impact of 3D printing design strategies based on different configurations of film,interdigitation,and framework on energy storage devices with a focus on ***,3D printing enables the rapid prototyping and production of batteries,reducing leading times and costs compared with traditional manufacturing ***,there are also challenges and limitations to consider,such as the need for further development of suitable 3D printing materials and processes for energy storage applications.

关键词： 3D printing battery commercialization bibliometric analysis electrode configurations zinc‐ion battery

依达拉奉与奥扎格雷钠联合治疗脑梗死的效果及对NIHSS评分影响

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罕少疾病杂志 2025年第1期32卷 23-25页

作者：夏中杰路雪燕位霞飞武帆张贵艺程璇新乡医学院第二附属医院河南新乡453002 郑州大学第一附属医院河南郑州450052

目的分析依达拉奉与奥扎格雷钠联合用药方案治疗脑梗死的临床效果及对患者NIHSS评分影响。方法选取我院2022年1月至2023年12月期间收治的120例脑梗死患者作为研究对象,遵循随机数字表法分组原则将患者分为参照组(60例)与实验组(60例)。... 详细信息

目的分析依达拉奉与奥扎格雷钠联合用药方案治疗脑梗死的临床效果及对患者NIHSS评分影响。方法选取我院2022年1月至2023年12月期间收治的120例脑梗死患者作为研究对象,遵循随机数字表法分组原则将患者分为参照组(60例)与实验组(60例)。参照组给予奥扎格雷钠治疗,.实验组在参照组基础上联合依达拉奉治疗。观察两.组治疗前后NIHSS评分、氧化.应激指标及疗效。结果.治疗后,.实验组NIHSS评分显著低于参照组(P<005);实验组氧化应激指标改善效果优于参照组(P<005);实验组治疗总有效率9667%高于参照组的8000%(P<005)。结论在脑梗死治疗中,依达拉奉与奥扎格雷钠联合治疗的效果更好,不仅可以更有效的改善患者神经功能,降低机体的氧化应激状态,同时也能提高临床治疗有效性,改善患者预后。

关键词：依达拉奉奥扎格雷钠脑梗死 NIHSS评分氧化应激指标疗效

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基于中西医临床病证特点的肺纤维化动物模型分析

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中国实验方剂学杂志 2021年第13期27卷 244-250页

作者：白明王赛谢逸轩张亚楠苗明三河南中医药大学药学院郑州450046

基于肺纤维化的临床病证特点,通过查阅相关文献,整理分析并建立肺纤维化的西医诊断标准与中医诊断标准,总结肺纤维化动物模型的造模诱导剂、造模方式、造模对象、造模机制、模型优缺点。分析其与中西医临床病证特点的吻合度,总结发现博... 详细信息

基于肺纤维化的临床病证特点,通过查阅相关文献,整理分析并建立肺纤维化的西医诊断标准与中医诊断标准,总结肺纤维化动物模型的造模诱导剂、造模方式、造模对象、造模机制、模型优缺点。分析其与中西医临床病证特点的吻合度,总结发现博来霉素气管内注射法为最常用造模方法且中西医临床吻合度较高,耗时短、模型稳定重复性高、成本低,适用于药物的快速筛选;其次为百草枯腹腔注射法,除吻合度较高外还具有成本低、易成模、造模易操作的优点,与百草枯中毒引起的肺纤维化病因一致,适用于探究百草枯中毒机制的研究和解救药物的研制。现有肺纤维化动物模型与西医临床病证吻合度较高,中医辨证标准不够明确,动物模型没有中医病机的体现。建立与中医病因病机相关、诊断标准更加精准鲜明的肺纤维化中医证型辨证标准是当下之需,加强与中医证型相关的肺纤维化实验研究,是日后努力的方向,期待以中西医结合的方式对肺纤维化更加深入的研究。

关键词：肺纤维化(PF) 动物模型病证结合

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齿轮箱耦合系统三维接触非线性动态特性仿真

东北大学学报（自然科学版） 2014年第1期35卷 79-83页

作者：梁明轩袁惠群李岩于印鑫东北大学机械工程与自动化学院辽宁沈阳110819 东北大学理学院辽宁沈阳110819

针对现有齿轮传动系统动力学模型和研究方法的不足,提出了基于完全弹性体的齿轮传动系统动态分析方法.以某型船用齿轮箱传动系统为研究对象,基于显式动力学有限元法,考虑部件之间的耦合作用建立了箱体-轴承-斜齿轮副三维动态接触非线性... 详细信息

针对现有齿轮传动系统动力学模型和研究方法的不足,提出了基于完全弹性体的齿轮传动系统动态分析方法.以某型船用齿轮箱传动系统为研究对象,基于显式动力学有限元法,考虑部件之间的耦合作用建立了箱体-轴承-斜齿轮副三维动态接触非线性模型.对整体齿轮箱传动系统进行了动态仿真,得到了关键部件的动力学特性,并与非耦合模型动态性能仿真结果进行比较.结果表明:滚动体与齿面应力呈不均匀分布,部件间的耦合作用加剧了齿轮箱的冲击效应.最后采用赫兹线接触理论进行了验证.

关键词：耦合系统显式动力学非线性接触力动应力

纳米多壁碳管结构变化对其复合材料微波性能影响

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航空材料学报 2012年第6期32卷 90-95页

作者：曾国勋张海燕陈易明熊旋广东工业大学广州510006

采用不同温度热处理纳米多壁碳管,研究纳米多壁碳管结构变化对相应复合材料的微波特性的影响。采用拉曼光谱分析表征纳米多壁碳管热处理前后的结构变化;测试纳米多壁碳管/石蜡复合材料在0.5～6GH介电谱。结果显示,热处理温度≤1000℃,... 详细信息

采用不同温度热处理纳米多壁碳管,研究纳米多壁碳管结构变化对相应复合材料的微波特性的影响。采用拉曼光谱分析表征纳米多壁碳管热处理前后的结构变化;测试纳米多壁碳管/石蜡复合材料在0.5～6GH介电谱。结果显示,热处理温度≤1000℃,纳米多壁碳管的ID/IG值基本不变,相应复合材料的复介电常数大致相等且吸波性能基本相同;热处理温度>1000℃,ID/IG值明显减小,内部结构发生重排,纳米多壁碳管平均晶粒尺寸增大,相应的纳米多壁碳管复合材料的复介电常数无论实部还是虚部均明显下降,微波吸收峰向高频移动。通过热处理控制纳米多壁碳管的ID/IG值和平均晶粒尺寸,可以调整纳米多壁碳管复合材料的微波介电谱,达到调整纳米多壁碳管复合材料的微波吸收特性的目的。

关键词：纳米多壁碳管结构介电谱拉曼谱

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基于信息熵的专家聚类赋权方法

控制与决策 2011年第1期26卷 153-156页

作者：周漩张凤鸣惠晓滨李克武空军工程大学工程学院西安710038

鉴于群组决策专家赋权方法研究中,现有赋权方法虽然考虑了专家给出的排序向量的一致性,但缺乏对排序向量信息相似性的度量,导致可能出现排序向量与群体共识相近,但信息不确定性较大的专家被赋予了与其他专家相同权重的问题.基于此,提出... 详细信息

鉴于群组决策专家赋权方法研究中,现有赋权方法虽然考虑了专家给出的排序向量的一致性,但缺乏对排序向量信息相似性的度量,导致可能出现排序向量与群体共识相近,但信息不确定性较大的专家被赋予了与其他专家相同权重的问题.基于此,提出一种基于信息熵的专家聚类赋权方法,运用信息相似系数对排序向量进行聚类分析,根据聚类结果和排序向量的信息熵来确定专家的权重.具体算例表明,该方法有效且可行.

关键词：熵信息相似系数聚类分析

The transcriptome of circulating cells indicates potential biomarkers and therapeutic targets in the course of hypertension-related myocardial infarction

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Genes & Diseases 2021年第4期8卷 555-568页

作者： Zilun Wei Yining Yang Qiaoling Li Yong Yin Zhonghai Wei Wenfeng Zhang Dan Mu Jie Ni xuan Sun Biao Xu Department of Cardiology Nanjing Drum Tower HospitalClinical College of Nanjing Medical UniversityNanjingJiangsu Province210008PR China Department of Cardiology Nanjing Drum Tower HospitalNanjing University Medical SchoolNanjingJiangsu Province210008PR China

Hypertension(HT)is the most common public-health challenge andshows a high inci-dence around the *** diseases are the leadingcause of mortality and morbidity among the elderly(age>65 years)in the ***,there is widespread acceptanceof the causal link between HT and acute myocardial infarction(MI).This is the first data-mining study to identify co-expressed differentially expressed genes(Co-DEGs)between HT and MI(rela-tive to nommal control)and to uncover potential biomarkers and therapeutic targets of HT-related *** thismanuscript,HT-specfcDEGs andMl-specific DEGs and dffretially expressed microRNAs(DE-miRNAs)were identifhed in Gene Expression Omnibus(GEO)datasets GSE24752,GSE60993,GSE62646,and GSE24548 after data consolidation and batch ***-quently,enichmentin Gene Ontology(GO)terms and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways as well as protein-protein interaction networks were identified,and single-gene gene set enrichment analysis was performed to determine the affected biological cate-gories and ***-matching of the results on cCo-DE-miRNAs and predicted miRNAs tar-geting the Co-DEGs wasconducted and discussed as *** found thatMYC and HIST1H2BO may be associatedwith HT,whereas FCGR 1A,FYN,KLRD1,KLRB1,and FOLR3 may be implicated in ***,Co-DEGs FOLR3 and NFE2 with predicted miRNAs and DE-miRNAs,especially miR-7 and miR-548,may be significantly associated and show huge potential as a new set of novel bio-markers and important molecular targets in the course of HT-related MI.

关键词： Biological function Blood Hypertension Microarray Myocardial infarction Pathway