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某核电厂汽轮机高压调节阀阀杆断裂原因分析

汽轮机技术 2024年第4期66卷 294-298,282页

作者：杜爱国杨兴旺李清泉江苏核电有限公司连云港222042

某核电厂汽轮机高压调节阀阀杆发生断裂,采用化学成分分析、力学性能分析、金相检验、扫描电镜观察、能谱分析以及力学分析等方法,分析了阀杆断裂的原因。结果表明阀杆断裂失效类型为高周疲劳开裂,阀杆与球头连接焊缝及热影响区硬度偏高... 详细信息

某核电厂汽轮机高压调节阀阀杆发生断裂,采用化学成分分析、力学性能分析、金相检验、扫描电镜观察、能谱分析以及力学分析等方法,分析了阀杆断裂的原因。结果表明阀杆断裂失效类型为高周疲劳开裂,阀杆与球头连接焊缝及热影响区硬度偏高,阀杆部分螺纹牙底圆弧半径过小,在阀芯受到汽流冲击引起的振动交变应力作用下,最终导致阀杆断裂。

关键词：阀杆断裂高周疲劳交变应力振动

A general solution for one dimensional chemo-mechanical coupled hydrogel rod

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Acta Mechanica Sinica 2018年第2期34卷 392-399页

作者： Xing-quan Wang qing-Sheng Yang Department of Engineering Mechanics Beijing University of Technology

Smart hydrogels are environmentally sensitive hydrogels, which can produce a sensitive response to external stimuli, and often exhibit the characteristics of multi filed coupling. In this paper, a hydrogel rod under chemomechanical coupling was analytically studied based on a poroelastical model. The already known constitutive and governing equations were simplified into the one dimensional case, then two different boundary conditions were considered. The expressions of concentration, displacement,chemical potential and stress related to time were obtained in a series form. Examples illustrate the interaction mechanism of chemical and mechanical effect. It was found that there was a balance state in the diffusion of concentration and the diffusion process could lead to the expansion or the stress change of the hydrogel rod.

关键词： Chemo-mechanical coupling Analytical solution One dimensional hydrogel rod

THE CHARACTERISTICS AND ESTIMATION OF FLOW THROUGH A SINGLE ROUGH-WALLED FRACTURE

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Journal of Hydrodynamics 2012年第3期24卷 315-322页

作者： LIU qing-quan FAN Hong-guang Laboratory-of Environmental Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100190China

The flow through a single fracture is numerically studied by means of the Fluent Software. The results show that the roughness of the fracture significantly affects the hydraulic conductivity in the fracture as compared with the cubic law model widely used to describe the flow between two smooth parallel plates. A new model is proposed in this paper, the non-symmetric sinusoidal fracture model, to simulate the flow in a real fracture. This model involves two sinusoidal-varying walls with different phases to replace the flat planes in the cubic law model. The relationships between the effective hydraulic apertures and the phase retardation for different relative amplitudes and wavelengths are numerically investigated. A simple expression of the effective hydraulic aperture of the fracture is obtained, together with the law of the effective hydraulic aperture against the amplitude, the phase retardation and the wavelength of two sinusoidal-varying walls.

关键词： fracture seepage cubic law effective hydraulic aperture non-symmetric sinusoidal fracture

On the horizontal distribution of algal-bloom in Chaohu Lake and its formation process

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Acta Mechanica Sinica 2014年第5期30卷 656-666页

作者： Yuan-Ying Chen qing-quan Liu Laboratory for Mechanics in Fluid Solid Coupling System Institute of Mechanics Chinese Academy of Sciences

Based on the remote sensing images of algae, the present work analyzes the horizontal distribution characteristics of algal blooms in Chaohu Lake, China, which also reveals the frequency of algal blooms under different wind directions. Further, an unstructured-grid, three-dimensional finite-volume coastal ocean model （FVCOM） is applied to investigate the wind-induced currents and the transport pro- cess to explain the reason why algal blooms occur at the detected places. We first deduce the primary distribution of biomass from overlaid satellite images, and explain the formation mechanism by analyzing the pollution sources, and simulating the flow field and transportation process under prevailing wind over Chaohu Lake. And then, we consider the adjustment action of the wind on the corresponding day and develop a two-time scale approach to describe the whole formation process of algae horizontal distribution in Chaohu Lake. That is, on the longer time scale, i.e., during bloom season, prevailing wind determines the primary distribution of biomass by inducing the characteristic flow field; on the shorter time scale, i.e., on the day when bloom occurs, the wind force adjusts the primary distribution of biomass to form the final distribution of algal bloom.

关键词： Chaohu Lake Algal bloom Horizontal distri- bution - Wind-driven current Two-time scale process

基于HGWOP的自由振动响应下桥梁断面颤振导数识别

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工程力学 2024年第10期41卷 33-42页

作者：何旭辉段泉成严磊卢同庆中南大学土木工程学院湖南长沙410075 高速铁路建造技术国家工程实验室湖南长沙410075 轨道交通工程结构防灾减灾湖南省重点实验室湖南长沙410075

基于节段模型弯扭耦合自由振动风洞试验,在现有的最小二乘原理的基础上引入了一种新的基于粒子群算法(Particle Swarm Optimization,PSO)和灰狼算法(Grey Wolf Optimizer,GWO)的混合算法(hybrid GWO with PSO,HGWOP)以搜索相关参数,从... 详细信息

基于节段模型弯扭耦合自由振动风洞试验,在现有的最小二乘原理的基础上引入了一种新的基于粒子群算法(Particle Swarm Optimization,PSO)和灰狼算法(Grey Wolf Optimizer,GWO)的混合算法(hybrid GWO with PSO,HGWOP)以搜索相关参数,从而更加准确地识别桥梁断面的颤振导数。通过对理想平板和某大桥在三种加权矩阵下基于传统迭代法和HGWOP的颤振导数识别结果进行对比分析,发现HGWOP不仅能够避免初值敏感性问题,在某一阶模态信号衰减迅速时进行准确地参数搜索,还能在相对复杂的加权矩阵下进行更加稳定和准确地识别。该文提出了一种新的颤振导数识别方法,并为更加科学且复杂的加权矩阵的应用提供了可能。

关键词：桥梁工程颤振导数混合算法参数识别最小二乘法

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地塞米松罗哌卡因预防跟骨骨折切口并发症

中国矫形外科杂志 2024年第1期32卷 71-74页

作者：金文孙良业高庆郑权刘孝峰安徽医科大学附属六安市人民医院骨科安徽六安237000

[目的]探讨术中局部注射地塞米松联合罗哌卡因(dexamethasone ropivacaine,DR)预防跟骨骨折切口相关并发症的疗效。[方法]回顾性分析本院2.19年1月—2.2.年10月开放复位内固定治疗跟骨骨折136例(137足)的临床资料。根据医患沟通结果,68... 详细信息

[目的]探讨术中局部注射地塞米松联合罗哌卡因(dexamethasone ropivacaine,DR)预防跟骨骨折切口相关并发症的疗效。[方法]回顾性分析本院2.19年1月—2.2.年10月开放复位内固定治疗跟骨骨折136例(137足)的临床资料。根据医患沟通结果,68例(68足)术中切口周围注射DR(DR组),68例(69足)未注射DR(常规组)。比较两组围手术期资料。[结果]两组患者手术时间、切口长度、术中失血量的差异均无统计学意义(P>0.05)。DR组在术后切口肿胀时间[(4.7±1.1)d vs(6.8±2.9)d,P2.d,P2.d vs(8.5±2.1)d,P2.1.2.vs(8.4±1.1),P2.d,(4.8±1.3)vs(6.6±1.8),P2.vs(58/2.9),P=0.010],两组患者术后拆线时间的差异无统计学意义(P>0.05)。[结论]术中切口周围局部注射地塞米松联合罗哌卡因能有效减轻跟骨骨折患者术后疼痛,减少切口相关并发症的发生。

关键词：地塞米松罗哌卡因跟骨骨折切口并发症

Mg-8Gd-(0,3)Sm-0.5Zr合金的动态再结晶生长动力学

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材料热处理学报 2024年第1期45卷 166-174页

作者：朱利敏李全安陈晓亚张清河南科技大学材料科学与工程学院河南洛阳471023 有色金属新材料与先进加工技术省部共建协同创新中心河南洛阳471023 河南省有色金属材料科学与加工技术重点实验室河南洛阳471023

利用铸造法制备了Mg-8Gd-(0,3)Sm-0.5Zr合金,并进行了52.℃均匀化处理8 h,随后在温度为350~500℃及应变速率为0.002.1 s^(-1)的条件下进行热压缩试验,绘制并分析合金热压缩后的真应力-真应变曲线,构建其动态再结晶生长动力学双参数模型... 详细信息

利用铸造法制备了Mg-8Gd-(0,3)Sm-0.5Zr合金,并进行了52.℃均匀化处理8 h,随后在温度为350~500℃及应变速率为0.002.1 s^(-1)的条件下进行热压缩试验,绘制并分析合金热压缩后的真应力-真应变曲线,构建其动态再结晶生长动力学双参数模型,并分析了合金生长动力学曲线特点及显微组织特征。结果表明:两种合金在热压缩时均发生了动态再结晶,通过双参数模型绘制动态再结晶动力学曲线,发现在高温低应变速率热压缩时,在真应变约0.2.,合金的动态再结晶的体积分数迅速增加至90%以上。对比分析Sm元素添加后的动态再结晶动力学曲线,发现Sm元素促进动态再结晶的进行,尤其在高温低应变速率热压缩时,在变形初期Sm的促进作用更明显。

关键词： Mg-8Gd-(0,3)Sm-0.5Zr合金热压缩动态再结晶

What enlightenment has the development of lung cancer bone metastasis brought in the last 2. years

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World Journal of Clinical Oncology 2024年第6期15卷 765-782页

作者： Yi Chen Xiao-Song Chen Rong-quan He Zhi-Guang Huang Hui-Ping Lu Hong Huang Da-Ping Yang Zhong-qing Tang Xia Yang Han-Jie Zhang Ning Qv Jin-Liang Kong Gang Chen Department of Pathology The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina Department of Medical Oncology The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina Department of Respiratory and Critical Care Medicine The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina Department of Pathology Guigang People’s Hospital of Guangxi/The Eighth Affiliated Hospital of Guangxi Medical UniversityGuigang 537100Guangxi Zhuang Autonomous RegionChina Department of Pathology Wuzhou Gongren Hospital/The Seventh Affiliated Hospital of Guangxi Medical UniversityWuzhou 543000Guangxi Zhuang Autonomous RegionChina

BACKGROUND Lung cancer bone metastasis(LCBM)is a disease with a poor prognosis,high risk and large patient *** considerable scientific output has accumulated on LCBM,problems have emerged,such as confusing research *** To organize the research frontiers and body of knowledge of the studies on LCBM from the last 2. years according to their basic research and translation,clinical treatment,and clinical diagnosis to provide a reference for the development of new LCBM clinical and basic *** We used tools,including R,VOSviewer and CiteSpace software,to measure and visualize the keywords and other metrics of 1903 articles from the Web of Science Core *** also performed enrichment and proteinprotein interaction analyses of gene expression datasets from LCBM cases *** Research on LCBM has received extensive attention from scholars worldwide over the last 2. *** therapies and immunotherapies have evolved into the mainstream basic and clinical research *** basic aspects of drug resistance mechanisms and parathyroid hormone-related protein may provide new ideas for mechanistic study and improvements in LCBM *** produced molecular map showed that ribosomes and focal adhesion are possible pathways that promote LCBM *** Novel therapies for LCBM face animal testing and drug resistance *** focus should centre on advancing clinical therapies and researching drug resistance mechanisms and ribosome-related pathways.

关键词： Lung cancer Bone metastasis Bibliometrics Targeted therapy Immunotherapy Enrichment analysis

亲缘关系异质性、家族所有权涉入与企业金融化——基于中国家族上市企业的经验数据

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金融论坛 2024年第2期29卷 37-47页

作者：谭庆美渠璨曹桂全游太美天津大学管理与经济学部天津300072

本文以2.08-2.2.年中国家族上市企业为研究样本,探讨家族高管亲缘关系异质性对企业金融化的影响及家族所有权涉入的调节效应。研究发现:亲缘关系异质性对企业金融化具有显著正向影响,家族所有权涉入程度提高会弱化二者之间的正相关关系... 详细信息

本文以2.08-2.2.年中国家族上市企业为研究样本,探讨家族高管亲缘关系异质性对企业金融化的影响及家族所有权涉入的调节效应。研究发现:亲缘关系异质性对企业金融化具有显著正向影响,家族所有权涉入程度提高会弱化二者之间的正相关关系;延伸型社会情感财富及高管团队短视对亲缘关系异质性与企业金融化之间的关系均具有部分中介效应;在儒家文化和宗族文化氛围较弱的家族企业中,亲缘关系异质性对企业金融化的正向影响更为显著;亲缘关系异质性增强带来的金融化倾向会对企业价值产生不利影响。

关键词：家族企业企业金融化亲缘关系异质性家族所有权涉入