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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)

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

Catheter ablation of atrial fibrillation in a patient with dextrocardia： what is the challenge？

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Chinese Medical Journal 2010年第17期123卷 2478-2479页

作者： WANG Xin-hua SHI Hai-feng HAN Bing TAN hong-wei jiang wei-feng LIU Xu Department of Cardiology Shanghai Chest Hospital Affiliated to Shanghai Jiao Tong University Shanghai 200030 China

Catheter ablation has been an established strategy for treating paroxysmal atrial fibrillation （AF）.Pulmonaryvein isolation is the predominant approach of catheter ablation. This procedure is characterized as transseptal catheterization and point-by-point ablation around the ipsilateral pulmonary veins （PVs）. Although catheter ablation can be safely performed in a heart with normal structures, it may be challenging to be performed in a dextrocardia.

关键词： atrial fibrillation catheter ablation structures strategy approach heart PVs

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

Transvenous embolization of cavernous dural arteriovenous fistula:report of 28 cases

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Chinese Medical Journal 2007年第24期120卷 2229-2232页

作者： HE hong-wei jiang Chu-han WU Zhong-xue LI You-xiang WANG Zhong-cheng Department of Neuroradiosurgery Beijing Neurosurgery InstituteBeijing Tiantan Hospital Capital Medical University Beijing100050 China

Background Usually, cavernous dural arteriovenous fistula can be treated via transarterial approaches. However, in many complicated patients, transvenous approaches are superior to the transarterial ones because of the difficulties during a transarterial operation. In this study, we retrospectively analyzed the outcomes of 28 patients with cavernous dural arteriovenous fistula treated by transvenous embolization. Methods From September 2001 to December 2005, 28 patients with 31 cavernous dural arteriovenous fistulae were treated with transvenous embolization in Beijing Tiantan Hospital. The involved cavernous sinuses were catheterized via the femoral vein-inferior petrosal sinus approach or the femoral-facial-superior ophthalmic vein approach, and embolized with coils （GDC, EDC, Matrix, Orbit or free coil） or coils plus silk. The patients were followed up for 3 to 26 months. Results All the 31 cavernous sinuses in the 28 patients were successfully embolized. Complete angiographic obliteration of the fistulae was achieved immediately in 25 patients. Residual shunting was observed in the other 3, who had drainage through the pterygoid plexus （2 patients） or the inferior petrosal sinus （1） after the operation. Headache and vomiting were the most common symptoms after the embolization. In 3 patients, who achieved complete angiographic obliteration immediately, the left oculomotor nerve palsy remained unchanged after the operation. Transient abducens nerve palsy was encountered in 1. In 1 patient, the occular symptoms were improved after the operation, but recurred 4 days later, and then disappeared spontaneously after 5 days. During the follow-up, no patient had recurrence. Three months after the operation, angiography was performed on the 3 patients with residual shunting. Two of them had angiographic cure, the other had residual drainage through the pterygoid plexus. Conclusions Transvenous catheterization and embolization of the cavernous sinus is a safe and ef

关键词： transvenous cavernous sinus dural arteriovenous fistula embolization

Tissue inhibitor of metalloproteinase-1 counteracts glucolipotoxicity in the pancreatic β-cell line INS-1

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Chinese Medical Journal 2011年第2期124卷 258-261页

作者： jiang hong-wei ZHU Han-yu WANG Jian-zhong FU Bo LU Yang hong Quan XIE Yuan-sheng CHEN Xiang-mei Institute of Nephrology General Hospital of Chinese People's Liberation Army Beijing 100853 China Department of Endocrinology and Metabolism First Affiliated Hospital Henan University of Science and Technology Luoyang Henan 471003 China

Background Glucolipotoxicity might play an important role in the β cell decompensation stage during the development of obesity-associated type 2 *** inhibitor of metalloproteinase-1 （TIMP-1） inhibits matrix metalloproteinase （MMP） activity and regulates proliferation and apoptosis of a variety of cell types,including pancreatic β-*** the present study,we investigated whether TIMP-1 counteracts glucolipotoxicity in the pancreatic β-cell line *** INS-1 cells were incubated in normal or high glucose,with or without palmitate （0.4 mmol/L）,in the presence of TIMP-1 or MMP inhibitor *** some experiments,cells were pretreated with phosphatidylinositol-3 （Pl-3） kinase inhibitor,LY294002 or *** amount of dead INS-1 cells was determined by HO342 and propidium iodide *** phosphorylation was evaluated by Western blotting analysis to investigate a possible mechanism of TIMP-1＇s *** TIMP-1 protected INS-1 cells from glucolipotoxicity independent of MMP ***-1 stimulated Akt *** of the PI-3 kinase pathway abolished the survival effect of *** TIMP-1 may counteract glucolipotoxicity induced β-cell death via a PI-3 kinase pathway.

关键词： glucolipotoxicity tissue inhibitor of metalloproteinase-1 pancreatic β-cell line INS-1