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某钢箱梁悬索桥加固方案设计与分析

公路 2024年第3期69卷 104-110页

作者：姜宏维郭建明中国公路工程咨询集团有限公司北京市100089 公路建设与养护技术、材料及装备交通运输行业研发中心北京市100097 中交集团公路路面养护技术研发中心北京市100097 中咨公路养护检测技术有限公司北京市100097

在大跨度钢箱梁悬索桥建设发展初期,设计和施工理念的不完善,造成在部分悬索桥运营过程中钢箱梁发生开裂现象,影响桥梁的安全运营。以某座主跨为1 108 m的单跨钢箱梁悬索桥为例,采用有限元软件ANSYS板壳单元建立该桥节段静力分析模型,... 详细信息

在大跨度钢箱梁悬索桥建设发展初期,设计和施工理念的不完善,造成在部分悬索桥运营过程中钢箱梁发生开裂现象,影响桥梁的安全运营。以某座主跨为1 108 m的单跨钢箱梁悬索桥为例,采用有限元软件ANSYS板壳单元建立该桥节段静力分析模型,得到开裂位置精细化受力分析结果,明确了钢箱梁开裂原因。在此基础上,提出了3种加固措施,并对3种措施进行了方案组合,结果表明,当3种措施同时作用于钢箱梁上时,可以有效地减小开裂处的应力,从而达到加固处治效果。

关键词：桥梁工程钢箱梁悬索桥钢箱梁开裂应力集中加固设计

基于K均值+Davies—Bouldin指数+PCA法的桥梁结构性能综合评估算法研究

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公路 2024年第4期69卷 124-132页

作者：姜宏维程雨段志中国公路工程咨询集团有限公司北京市100089 公路建设与养护技术、材料及装备交通运输行业研发中心北京市100097 中交集团公路路面养护技术研发中心北京市100097 中咨公路养护检测技术有限公司北京市100097

旨在提供一种确定评估桥梁结构构件性能的多参数综合评估算法模型,以指导桥梁结构体系的养护决策,确保其安全运行。首先,采用结构非线性分析方法,确定双层桁架系杆拱桥结构在极限状态下各构件的理论承载能力阈值。然后,基于聚类分析方法... 详细信息

旨在提供一种确定评估桥梁结构构件性能的多参数综合评估算法模型,以指导桥梁结构体系的养护决策,确保其安全运行。首先,采用结构非线性分析方法,确定双层桁架系杆拱桥结构在极限状态下各构件的理论承载能力阈值。然后,基于聚类分析方法,采用改进的K均值法及Davies—Bouldin指数法对桥梁性能进行评估,利用主成分分析法对多参数进行关键因素的综合评估。最后,通过某双层桁架系杆拱桥实例进行验证,验证了对运营阶段拉索性能提出的评估方法的有效性与合理性。结果表明,提出的优化评估方法能有效地反映拉索结构的性能变化情况,为桥梁养护决策提供新的思路。

关键词：桥梁工程系杆拱桥结构非线性分析性能评估聚类分析 Davies—Bouldin指数主成分分析(PCA)

基于传播动力学模型的超大型城市新发突发高致病性呼吸道传染病应对策略研究

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中国感染控制杂志 2024年第10期23卷 1264-1270页

作者：罗佳瑶雷志群闫小龙王秋月王睿蒋红卫魏晟华中科技大学同济医学院公共卫生学院流行病与卫生统计学系湖北武汉430030 南方科技大学公共卫生与应急管理学院广东深圳518055

目的探索中国超大型城市应对新发突发高致病性呼吸道传染病暴发时不同干预策略的效果,为有效应对新发突发呼吸道传染病提供决策依据。方法构建易感-潜伏-感染-移出(SEIR)传播动力学模型,参考既往多种新发呼吸道传染病的致病性和传染性参... 详细信息

目的探索中国超大型城市应对新发突发高致病性呼吸道传染病暴发时不同干预策略的效果,为有效应对新发突发呼吸道传染病提供决策依据。方法构建易感-潜伏-感染-移出(SEIR)传播动力学模型,参考既往多种新发呼吸道传染病的致病性和传染性参数,并将其进行组合。模拟低、中、高传染性的新发突发高致病性呼吸道传染病在中国1000万人口超大型城市暴发的场景下,比较实施不同非药物干预措施(NPIs)组合应对暴发后100 d内疫情的发展情况。结果高致病性新发呼吸道传染病暴发时,如果其传染性较低(R 0约为1.5),无需采取严格的NPIs就可以控制疫情。若其传染性为中等(R 0约为6),则需要根据其已有的感染规模采取不同强度的NPIs:在初始感染人数为50例时,采取中等强度的NPIs,100 d内可将感染及死亡比例控制在较低水平,病例所需住院床位控制在全国平均储备水平以下;但在已有感染规模超过100例时,则需要采取高强度的NPIs才能控制疫情发展。在其传染性极强(R 0约为10)的情况下,无论感染规模如何,应立即采取高强度NPIs才能有效控制疫情发展及感染、死亡规模。结论在面对新发高致病性呼吸道传染病暴发时,尽早根据其流行病学特征及感染规模采取合适的NPIs,才能最大限度降低其对人群健康的危害。

关键词：呼吸道传染病传播动力学非药物干预措施超大型城市新发传染病

Micro-porous TiO2 thin films grown on surface of Ti substrate

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中国有色金属学会会刊：英文版 2004年第z1期14卷 178-181页

作者： WU Xiao-hong QIN wei jiang Zhao-hua HU Xin-guo Li Qing-fen Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China School of Mechanics and Electronics Engineering Harbin Engineering University Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China School of Mechanics and Electronics EngineeringHarbin Engineering University Harbin 150001 China

Microporous titanium dioxide thin films have been grown on titanium plates by the micro-plasma oxidation method with different current densities (4, 6, 10 and 14 A/dm2). X-ray diffraction, scanning electronic microscopy and UV-Vis spectrophotometry were used to characterize the films. It is found that the films grown are microporous and consist of crystalline titanium dioxide. The micropore size and the content of anatase and rutile TiO2 phase increase with the applied voltage. The relatively higher degradation efficiency for rhodamine B is obtained in the film produced with a current density of 10 A/dm2.

关键词： micro-plasma oxidation TiO2 thin film photo-catalytic activity rhodamine B

An AES Study of Initial Oxidation of Ce-La Alloy at Room Temperature and Low Oxygen Pressure

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Journal of Rare Earths 2004年第Z1期22卷 18-21页

作者： Yang jiangrong Wang Xiaolin Xiao hong Zhou wei jiang Chunli Lu Lei China Academy of Engineering Physics Mianyang 621900 China China Academy of Engineering Physics Mianyang 621900 China China Academy of Engineering Physics Mianyang 621900 China China Academy of Engineering Physics Mianyang 621900 China China Academy of Engineering Physics Mianyang 621900 China China Academy of Engineering Physics Mianyang 621900 China

Auger Electron Spectroscopy was used to characterize the initial stages of the oxidation of Ce-5% La alloy in an oxygen atmosphere at low pressure( ～ 10-6 Pa) and room temperature after the surface is cleaned by Ar+ ion *** is shown that exposure of clean cerium to oxygen causes the appearance and development of three new Auger peaks at 97,662 and 676 eV, which steadily grow during oxidation of *** oxygen dose less than 20 L,a semi-protective layer of oxide forms on the surface of cerium and its growth follows a logarithmic *** further exposure of oxygen, the oxide film grown in the previous stage becomes thicker and the uptake of oxygen reaches saturation at oxygen exposure of 25 L,and the oxide film mainly consists of Ce2O3.

关键词： Auger electron spectroscopy oxidation Ce-La alloy rare earths

Coupling analysis method of grouting construction with deformation response of adjacent existing tunnel

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Underground Space 2024年第2期15卷 312-330页

作者： Ping-wei jiang Zhi-hong Zhang hong Zheng Jin-kun Huang Key Laboratory of Urban Security and Disaster Engineering of China Ministry of Education Beijing University of TechnologyBeijing 100124China China MCC17 Group Co.LTD MaanshanAnhui 243000China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

In the new tunnel under close distance through the existing tunnel risk source,the grouting scheme developed to compensate for stratum losses is still based on empirical methods,relying on the overburden thickness of existing *** can potentially lead to an excessively high or low probability of uplift of existing *** a coupled deformation analysis method between the grouting construction and adjacent existing tunnels is of great theoretical significance for developing grouting *** order to reasonably limit the design parameters of grouting construction,based on the theory of fluid–solid coupling elastic pore-column expansion and the theory of random media,the calculation method of stratum displacement which simultaneously considers the coexistence of grout compaction expansion and permeability diffusion mode is derived,and the accuracy of the calculation method is verified by engineering *** accuracy of this calculation method was verified through engineering *** with the deformation coordination condition,the existing tunnel is regarded as an elastic Euler-Bernoulli continuous beam,and the finite element coupling balance equation of the interaction between the existing tunnel and the surrounding soil is *** on this,a coupling calculation model of the grouting construction and the deformation response of the adjacent existing tunnel is *** with three times of grouting construction examples in the shield tunneling project of Beijing Metro Line 12 under the existing airport line,the reliability of the coupling calculation model to determine the grouting construction parameters is *** calculation parameters in the coupling calculation model have clear physical meanings,which can provide a theoretical basis for the grouting design of similar risk source projects.

关键词： Grouting Close-range underpass Tunnel Random medium theory Euler-Bernoulli continuous beam

Elevated Arsenic Exposure Is Associated with an Increased Risk of Chronic Hepatitis B Virus Infection： NHANES （2003-2014） in U.S. Adults

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Current Medical Science 2018年第4期38卷 610-617页

作者： wei-hua ZHANG Jiao HUANG Mei FENG Ye-qing TONG Xu-hua GUAN hong-wei jiang Sheng wei Department of Epidemiology and Biostatistics Key Laboratory of Environment and Health of Ministry of Education School of Public Health Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China Department of Preventive Medicine School of Medicine Ningbo University Ningbo 315211 China Institute of Infectious Disease Control and Prevention Hubei Provincial Center for Disease Control and Prevention Wuhan 430079 China

Studies concerning the association between arsenic exposure and hepatitis B virus （HBV） infection have been lacking. The present study aimed to examine the association between total urinary arsenic （TUA） and infection ofHBV. A total of 5186 participants from National Health and Nutrition Examination Survey （NHANES） 2003-2014 were included in the analysis. We used logistic regression to evaluate the association. We defined two measures of TUA. TUA1 was the sum of arsenous acid, arsenicacid, monomethylarsonic acid and dimethylarsenic acid. TUA2 was defined as TUA minus arsenobetaine and arsenocholine. The results showed that the weighted overall prevalence of HBV infection was 6.08%. For NHANES 2003-2014, the medians （interquartile range） of TUA1 and TUA2 were 5.60 μg/L （3.97-8.09 μg/L） and 4.91 μg/L （2.36-9.11 μg/L）, respectively. Comparing the highest quartile to the lowest quartile after multivariable adjustment showed that the odds ratios （ORs） and 95% confidence intervals （CIs） for TUA1 and TUA2 were 2.44 （1.40-4.27） and 2.84 （1.60-5.05）, respectively. In conclusion, elevated urinary arsenic was associated with the risk of HBV infection. Further studies, especially prospective studies, are needed to confirm the causal relationship between arsenic exposure and HBV infection.

关键词： arsenic exposure hepatitis B infection National Health and Nutrition Examination Survey

椅旁CAD/CAM高嵌体修复老年磨牙大面积缺损的临床观察

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口腔颌面修复学杂志 2024年第1期25卷 28-32页

作者：汪成君唐俊婍王梅蒋红卫杭州医学院附属义乌医院口腔科义乌322000 义乌市中心医院口腔科义乌322000

目的:探究数字化椅旁计算机辅助设计/计算机辅助制造(CAD/CAM)高嵌体对老年磨牙大面积缺损患者的修复效果。方法:选取2016年7月~2020年6月本院收治的75例(75颗缺损牙)老年磨牙大面积缺损患者,行根管治疗后采用椅旁CAD/CAM进行高嵌体修... 详细信息

目的:探究数字化椅旁计算机辅助设计/计算机辅助制造(CAD/CAM)高嵌体对老年磨牙大面积缺损患者的修复效果。方法:选取2016年7月~2020年6月本院收治的75例(75颗缺损牙)老年磨牙大面积缺损患者,行根管治疗后采用椅旁CAD/CAM进行高嵌体修复。评价修复后12、24个月的修复效果,并于修复后24个月调查患者满意度,检测修复前和修复后12、24个月的龈沟液内肿瘤坏死因子-α(TNF-α)和基质金属蛋白酶8(MMP-8)水平。结果:修复后12、24个月的修复合格率分别为97.33%、93.33%,修复后24个月患者在修复体颜色、外形及舒适度三方面的满意率分别为98.67%、97.33%、100%。修复后12、24个月的患牙龈沟液内TNF-α及MMP-8水平较修复前下降(P<0.05)。结论:CAD/CAM技术制作的高嵌体对于老年磨牙大面积缺损的修复效果良好,患者满意度高,可作为老年磨牙大面积缺损的有效治疗方案。

关键词：椅旁CAD/CAM 老年牙体缺损高嵌体修复

Processing of a low-costγ-γ'NiPtAl coating with improved oxidation resistance

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Rare Metals 2024年第6期43卷 2832-2841页

作者： Yan jiang Liang-Liang wei Jian He hong-Bo Guo School of Materials Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of High-Temperature Structural Materials and Protective Coatings Ministry of Industry and Information TechnologyBeihang UniversityBeijing 100191China

A novelγ-γ'(Ni solid solution—Ni_(3)Al)NiPtAl coating was produced on advanced single-crystal(SC)superalloy N5 by electroplating of a thin Pt coating with~3μm in thickness followed by heat treatment at 1000℃in *** comparison,a traditionalγ-γ'NiPtAl coating was also produced by electroplating of a thick Pt coating with~6μm in thickness followed by heat treatment at 1100℃in *** novel coating has a mass gain of~0.5 mg·cm^(-2)after 100 h 1-h cyclic oxidation at 1150℃,showing better oxidation resistance than the traditional *** oxide scale mostly consisting ofα-Al_(2)O_(3)grew on the novel coating because the element Cr from the SC alloy substrate contributes to the formation ofα-Al_(2)O_(3).Pt content in the novel coating has significant effect on the oxidation *** optimized Pt content in the coating is about 16 at%,which is helpful to reduce the diffusion of harmful elements from the substrate into the coating but also to reduce the cost of the coating.

关键词： γ-γ'NiPtAl coating Platinum Oxidation Al_(2)O_(3) Superalloy