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Flaring activity from quiescent states in neutron-star X-ray binaries
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作者 Dimitris M.Christodoulou Silas G.T.Laycock +1 位作者 Demosthenes Kazanas Ioannis Contopoulos 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第11期123-132,共10页
We examine systematically the observed X-ray luminosity jumps(or flares) from quiescent states in millisecond binary pulsars(MSBPs) and high-mass X-ray binary pulsars(HMXBPs). We rely on the published X-ray light curv... We examine systematically the observed X-ray luminosity jumps(or flares) from quiescent states in millisecond binary pulsars(MSBPs) and high-mass X-ray binary pulsars(HMXBPs). We rely on the published X-ray light curves of seven pulsars: four HMXBPs, two MSBPs and the ultraluminous X-ray pulsar M82 X-2. We discuss the physics of their flaring activities or lack thereof, paying special attention to their emission properties when they are found on the propeller line, inside the Corbet gap or near the light-cylinder barrier. We provide guiding principles for future interpretations of faint X-ray observations, as well as a method of constraining the propeller lines and the dipolar surface magnetic fields of pulsars using a variety of quiescent states. In the process, we clarify some disturbing inaccuracies that have made their way into the published literature. 展开更多
关键词 aCCRETiON accretion disks pulsars: individual(4U 0115+63 V 0332+53 M82 X-2 aquila X-1 SaX j1808.4–3658 aX j0049.4–7323 1a 0535+262) stars: magnetic fields stars: neutron X-rays: binariesà?g
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Singchia and Gunnaria,two new genera of Orchidaceae 被引量:3
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作者 Zhong-Jian LIU Li-Jun CHEN 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第6期599-604,共6页
Singchia Z. J. Liu & L. J. Chen, a new orchid genus, is established based on the new species S. malipoensis Z. J. Liu & L. J. Chen found in southeast Yunnan, China. The new genus is related to Pteroceras, from which... Singchia Z. J. Liu & L. J. Chen, a new orchid genus, is established based on the new species S. malipoensis Z. J. Liu & L. J. Chen found in southeast Yunnan, China. The new genus is related to Pteroceras, from which it differs by having a lip with its basal margins immovably adnate to the lower part of the pendent column foot, a thin-walled spur, and very unequally and deeply split pollinia, each with a distinct caudicle. In addition to a discussion on Ascocentrum pusillum, a species of questionable placement, another new genus, namely Gunnaria S. C. Chen ex Z. J. Liu & L. J. Chen, is set up and a new combination, namely G. pusilla (Aver.) Z. J. Liu & L. J. Chen, is made. The new genus Gunnaria differs from its allyAscocentrum by having a cross-shaped pollinarium, sulcate or split pollinia, each with a distinct caudicle attached to a common linear stipe much longer than either pollinia or viscidium, and strongly incurved side lobes of the lip. 展开更多
关键词 China g. pusilla aver.) Z. j. Liu L. j. Chen gunnaria S. C. Chen ex Z. j. Liu L. j. Chen new combination new genera new species S. malipoensis Z. j. Liu L. j. Chen Singchia Z. j. Liu L. j. Chen Yunnan.
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Historical Evidence for the Birth of the Newly Discovered Pulsar PSR J1833-1034
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作者 Zhen-Ru Wang Min Li Yi Zhao 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2006年第5期625-628,共4页
Stimulated by the recent discovery of PSR J1833-1034 in SNR G21.5-0.9 and its age parameters presented by two groups of discovery, we demonstrate that the PSR J1833- 1034 was born 2053 years ago from a supernova explo... Stimulated by the recent discovery of PSR J1833-1034 in SNR G21.5-0.9 and its age parameters presented by two groups of discovery, we demonstrate that the PSR J1833- 1034 was born 2053 years ago from a supernova explosion, the BC 48 guest star observed in the Western Han (Early Han) Dynasty by ancient Chinese. Based on a detailed analysis of the Chinese ancient record of the BC 48 guest star and the new detected physical parameters of PSR J1833-1034, agreements on the visual position, age and distance between PSR J1833- 1034 and the BC 48 guest star are obtained. The initial period/90 of PSR J1833-1034 is now derived from its historical and current observed data without any other extra assumption on P0 itself, except that the factor PP is a constant in its evolution until now. 展开更多
关键词 stars PULSaRS individual (PSR j 1833-1034) -- iSM supernova remnants individual g21.5-0.9) -- supernovae individual (BC 48 guest star) -- history of astronomy
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异常血红蛋白Hb J-Bangkok和Hb G-Coushatta的基因型与表型分析
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作者 裴元元 温丽娟 +1 位作者 冉健 魏凤香 《中国产前诊断杂志(电子版)》 2022年第4期28-31,共4页
目的分析2种β珠蛋白基因突变所致异常血红蛋白Hb J-Bangkok和Hb G-Coushatta的基因型及其血液学特征。方法收集深圳市龙岗区妇幼保健院2020年4至10月毛细管血红蛋白电泳检测出异常血红蛋白条带的病例4例,采用PCR-流式荧光杂交法及基因... 目的分析2种β珠蛋白基因突变所致异常血红蛋白Hb J-Bangkok和Hb G-Coushatta的基因型及其血液学特征。方法收集深圳市龙岗区妇幼保健院2020年4至10月毛细管血红蛋白电泳检测出异常血红蛋白条带的病例4例,采用PCR-流式荧光杂交法及基因测序方法进行基因诊断,对明确诊断的异常血红蛋白病例进行回顾性血液学参数分析。结果4个病例中检测到2种β珠蛋白基因突变,均为杂合子。3例为Hb J-Bangkok,血液学表型正常,血红蛋白电泳可见Hb A峰前Z12区有一条快速的异常血红蛋白;1例为Hb G-Coushatta,血液学表型未见异常,血红蛋白电泳Z(D)区有一条慢速异常血红蛋白。结论异常血红蛋白Hb J-Bangkok和Hb G-Coushatta的携带者均无小细胞低色素贫血的表现。毛细管电泳和基因测序技术联合应用,可以分辨和发现更多的异常血红蛋白。 展开更多
关键词 异常血红蛋白 Hb j-Bangkok Hb g-Coushatta
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The Physical Laws and Mathematical Axioms of the Brain’s OS and the Traditional Fundamental Laws of Thought of Logic and Philosophy
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作者 Leo Depuydt 《Advances in Pure Mathematics》 2021年第12期988-1039,共52页
This article presents four (4) additions to a book on the brain’s OS published by SciRP in 2015 [1]. It is a kind of appendix to the book. Some familiarity with the earlier book is presupposed. The book itself propos... This article presents four (4) additions to a book on the brain’s OS published by SciRP in 2015 [1]. It is a kind of appendix to the book. Some familiarity with the earlier book is presupposed. The book itself proposes a complete physical and mathematical blueprint of the brain’s OS. A first addition to the book (see Chapters 5 to 10 below) concerns the relation between the afore-mentioned blueprint and the more than 2000-year-old so-called fundamental laws of thought of logic and philosophy, which came to be viewed as being three (3) in number, namely the laws of 1) Identity, 2) Contradiction, and 3) the Excluded Middle. The blueprint and the laws cannot both be the final foundation of the brain’s OS. The design of the present paper is to interpret the laws in strictly mathematical terms in light of the blueprint. This addition constitutes the bulk of the present article. Chapters 5 to 8 set the stage. Chapters 9 and 10 present a detailed mathematical analysis of the laws. A second addition to the book (Chapter 11) concerns the distinction between the laws and the axioms of the brain’s OS. Laws are part of physics. Axioms are part of mathematics. Since the theory of the brain’s OS involves both physics and mathematics, it exhibits both laws and axioms. A third addition (Chapter 12) to the book involves an additional flavor of digitality in the brain’s OS. In the book, there are five (5). But brain chemistry requires a sixth. It will be called Existence Digitality. A fourth addition (Chapter 13) concerns reflections on the role of imagination in theories of physics in light of the ignorance of deeper causes. Chapters 1 to 4 present preliminary matter, for the most part a brief survey of general concepts derived from what is in the book [1]. Some historical notes are gathered at the end in Chapter 14. 展开更多
关键词 aristotle Boole g. Brain’s OS Fundamental Laws of Thought Kolmogorov a. N. Laws and axioms Leibniz g. W. Locke j. Logic PHiLOSOPHY Rational Human intelligence Venn j.
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Rain-Flow Modelling Using the GR4J Model for Flood Risk Management in the Oti Watershed (Togo)
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作者 Koungbanane Dambré Kodja Japhet Domiho +2 位作者 Lemou Faya Totin Vodounon Henri Sourou Amoussou Ernest 《Open Journal of Modern Hydrology》 CAS 2024年第4期213-230,共18页
In recent years, West Africa has been confronted with hydro-climatic disasters causing crises in both urban and rural areas. The tragedy in the occurrence of such events lies in the recurrent aspect of high water and ... In recent years, West Africa has been confronted with hydro-climatic disasters causing crises in both urban and rural areas. The tragedy in the occurrence of such events lies in the recurrent aspect of high water and associated floods. The devastating floods observed in Africa’s major rivers have revealed the need to understand the causes of these phenomena and to predict their behavior in order to improve the safety of exposed people and property. The aim of this study is to reproduce flood flows using the GR4J (Rural Engineering Four Daily Parameters) model to analyze flood risk in the Oti watershed in Togo. Daily data on flows (m3/s), potential evapotranspiration (mm/day) and average precipitation (mm) over the basin from 1961-2022 collected at the National Meteorological Agency of Togo (ANAMET) and the Department of Water Resources in Lome, were used with the R software package airGR. The Data from the West African Cordex program from 1961-2100 were used to analyze projected flows. The results obtained show the GR4J model’s effectiveness in reproducing flood flows, indicating that observed flows are well simulated during the calibration and validation periods, with KGE values ranging from 0.73 to 0.85 at calibration and 0.62 to 0.81 at validation. These KGE values reflect the good performance of the GR4J model in simulating flood flows in the watershed. However, a deterioration in the KGE value was observed over the second validation period. Under these conditions, there may be false or missed alerts for flood prediction, and the use of this model should be treated with the utmost caution for decision-support purposes. 展开更多
关键词 Modeling génie Rural à 4 Paramètres journaliers (gR4j) Floods Kling-gupta Efficiency (KgE) Oti Watershed Risk
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gkh jqx
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《新课程实验教材小一语文教案设计合订本》 2003年第2期7-7,共1页
关键词 g k H j Q X 教学目标 汉语拼音教学 小学 语文教学 教学方法 教学设计 人教版 一年级
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J2ME M3G中Animation的设计与实现
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作者 徐中礼 谢丹铭 +1 位作者 李冰峰 高传善 《计算机科学》 CSCD 北大核心 2007年第4期273-275,共3页
为了Java三维图形程序能在不同的移动设备和平台上运行,JCP(Java Community Process)制定了J2ME M3G(Mobile 3D Graphics API),规范了移动设备上Java三维图形程序的API和框架。而M3G中由于动画部分的独特性以及它在设计和实现中的复杂性... 为了Java三维图形程序能在不同的移动设备和平台上运行,JCP(Java Community Process)制定了J2ME M3G(Mobile 3D Graphics API),规范了移动设备上Java三维图形程序的API和框架。而M3G中由于动画部分的独特性以及它在设计和实现中的复杂性,我们结合在XORP上开发M3G类库经验的基础,总结并给出了其设计和实现的参考模型和理论基础,也适用于其它3D类库的设计和开发。 展开更多
关键词 jaVa jCP j2ME M3g 动画 XORP
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J2ME M3G中RayIntersection的设计与实现
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作者 徐中礼 李冰峰 高传善 《计算机工程》 CAS CSCD 北大核心 2007年第1期65-67,共3页
J2ME M3G(Mobile 3D Graphics API)规范了移动设备上Java三维图形程序的API和框架,使得符合M3G标准的Java程序能在不同的设备和平台上运行。由于M3G中RayIntersection在设计和实现中的复杂性,该文结合在XORP上开发M3G类库经验的基础,总... J2ME M3G(Mobile 3D Graphics API)规范了移动设备上Java三维图形程序的API和框架,使得符合M3G标准的Java程序能在不同的设备和平台上运行。由于M3G中RayIntersection在设计和实现中的复杂性,该文结合在XORP上开发M3G类库经验的基础,总结并给出了其设计和实现的参考模型和理论基础,并在此基础上重构了具体实现。 展开更多
关键词 j2ME M3g 框架 jaVa Rayintersection XORP 重构
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Coarse-grained description of q-deformation top and t-j model
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作者 陈景灵 王宙斐 +1 位作者 葛墨林 薛康 《Science China Mathematics》 SCIE 1998年第4期422-430,共9页
From RTT relations the integrable Hamiltonian of the trigonometric Goryachev\|Chaplygin gyrostat is established, which can be reduced to the Hamiltonian of t\|j model by using multi\|fermion realization of \%SU\-q(2)\... From RTT relations the integrable Hamiltonian of the trigonometric Goryachev\|Chaplygin gyrostat is established, which can be reduced to the Hamiltonian of t\|j model by using multi\|fermion realization of \%SU\-q(2)\% algebra and average\|field approximation. 展开更多
关键词 coarse\|grained DESCRiPTiON t\|j MODEL \%g\|C\% top.
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聚合物和纤维工厂建设的最新发展趋势——对Zimmer公司行政执行委员会成员W.J.Kr^mer和M.G.Mart博士的采访
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作者 王胜东 《国际纺织导报》 2002年第z2期36-39,共3页
关键词 Zimmer M.g.Mart W.j.Kr^mer 聚酯短纤维 聚合物 大分子化合物 博士
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基于SPCA556G卫星导航系统的JAVA软件平台移植
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作者 施楚 丁喜波 +2 位作者 刘辉 王佳 张菊 《佳木斯大学学报(自然科学版)》 CAS 2009年第1期85-87,99,共4页
介绍了Java编程语言的J2ME平台向凌阳SPCA556G平台的移植.在设计过程中首先对开发平台,GPS的定位原理,NMEA0183协议进行了了解.然后深入的分析了J2ME平台的结构,根据KVM和MIDP的各自特性分别进行移植,最终实现J2ME的移植要求.
关键词 j2ME SPCa556g 嵌入式技术
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从日式3G手机系统看Android系统之优势
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作者 高蕾 《电脑知识与技术》 2012年第4X期2743-2745,2755,共4页
日本的NTT DoCoMo公司是世界上第一个开通IMT-2000 3G的业务,它主要应用的是J2ME开发软件,利用Java技术的跨平台性和网络功能进行编写,应用IAppli执行环境运行程序。而Android系统是目前国内手机系统市场的主流,它根据输入操作的需要,... 日本的NTT DoCoMo公司是世界上第一个开通IMT-2000 3G的业务,它主要应用的是J2ME开发软件,利用Java技术的跨平台性和网络功能进行编写,应用IAppli执行环境运行程序。而Android系统是目前国内手机系统市场的主流,它根据输入操作的需要,选用一块全触屏作为其主要输入方式,实现多点触摸。Android系统不存在任何以往阻碍移动产业创新的专有权障碍,允许所有厂商和个人在其基础上进行开发,这一点是日式手机所不及的。我们通过对这两款系统进行比较,找出其优缺点,从而更好的为国内手机市场的发展服务。 展开更多
关键词 日本3g手机 NTT Do CoMo aNDROiD系统 iappli j2ME
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g(x)-J-clean环
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作者 沈磊 王芳贵 王茜 《四川师范大学学报(自然科学版)》 CAS 北大核心 2018年第4期483-488,共6页
设R是环,J(R)和C(R)分别表示R的Jacobson根与中心,g(x)∈C(R)[x]为一给定多项式.称R为g(x)-J-clean环,如果任何r∈R可表为r=s+j,其中j∈J(R)且g(s)=0.给出g(x)-J-clean环的基本性质,并给出一些J-clean环的等价刻画,考察(x3-x)-clean环与... 设R是环,J(R)和C(R)分别表示R的Jacobson根与中心,g(x)∈C(R)[x]为一给定多项式.称R为g(x)-J-clean环,如果任何r∈R可表为r=s+j,其中j∈J(R)且g(s)=0.给出g(x)-J-clean环的基本性质,并给出一些J-clean环的等价刻画,考察(x3-x)-clean环与弱clean环的关系,也证明(xn-1)-J*-clean环就是有限域. 展开更多
关键词 CLEaN环 g(x)-j-clean环 g(x)-clean环 j-clean环 弱clean环 有限域
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超声冲击功率对S355J2G4钢接头组织与性能的影响
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作者 武永利 杨志斌 +2 位作者 车彦龙 康金文 孙亚鹏 《焊接技术》 2024年第8期14-17,共4页
文中基于相同的超声冲击时间采用不同的超声冲击功率对机车车辆用S355J2G4钢焊接接头进行超声冲击处理,系统研究了超声冲击功率对接头微观组织、力学性能和耐磨性能的影响规律。试验结果表明:随超声冲击功率增加,接头表层塑性变形层厚... 文中基于相同的超声冲击时间采用不同的超声冲击功率对机车车辆用S355J2G4钢焊接接头进行超声冲击处理,系统研究了超声冲击功率对接头微观组织、力学性能和耐磨性能的影响规律。试验结果表明:随超声冲击功率增加,接头表层塑性变形层厚度增加且晶粒尺寸减小,但超声冲击功率过大将导致接头表层出现损伤;随超声冲击功率增加,接头表层硬度明显增加,但接头的拉伸性能无明显变化;随超声冲击功率增加,接头疲劳性能呈先增加后减小的趋势;随超声冲击功率增加,接头的耐磨性能明显提升。当超声冲击时间6 min时,超声冲击功率50%处理接头的综合性能最佳。 展开更多
关键词 S355j2g4钢 焊接接头 超声冲击 微观组织 力学性能 耐磨性能
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G20CrNi2MoA钢机械性能与末端淬透性关系研究
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作者 张成连 金宏伟 李艳芝 《黑龙江冶金》 2005年第4期6-7,共2页
本文通过试验研究,数理统计及金相分析找出了 G20crNi2MoA 钢机械性能与末端淬透性 J9硬度值之间的关系,并研究了以末端淬透性来保证钢机械性能的可行性。
关键词 g20CrNi2Moa钢机械性能 末端淬透性 拉力试验 j9点
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苦皮素G和苦皮素J的NMR数据解析 被引量:12
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作者 陈玉方 吴鸣建 +1 位作者 张海艳 赵天增 《河南科学》 2010年第1期33-37,共5页
对苦皮素G和J进行了1H和13C NMR检测,通过DEPT和1H-1HCOSY,HSQC,HMBC等2D NMR技术对这两个化合物所有的1H和13C NMR信号进行了详细解析和全归属.
关键词 NMR 归属 2D NMR 苦皮素g 苦皮素j
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S355J2G3低合金钢焊接接头的组织和力学性能 被引量:4
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作者 崔岩 鲁二敬 +2 位作者 吴晓明 张艳辉 吴昊 《机械工程材料》 CAS CSCD 北大核心 2012年第10期38-41,共4页
通过拉伸、冲击、弯曲、硬度和金相等试验对S355J2G3低合金钢MAG焊焊接接头的力学性能与显微组织进行了研究。结果表明:采用G38 3G3Si1焊丝对S355J2G3低合金钢进行焊接时,可获得拉伸、弯曲和冲击性能均良好的焊接接头;接头硬度的分布较... 通过拉伸、冲击、弯曲、硬度和金相等试验对S355J2G3低合金钢MAG焊焊接接头的力学性能与显微组织进行了研究。结果表明:采用G38 3G3Si1焊丝对S355J2G3低合金钢进行焊接时,可获得拉伸、弯曲和冲击性能均良好的焊接接头;接头硬度的分布较均匀,最高不大于380HV;焊缝组织为沿柱状晶晶界析出的块状先共析铁素体,晶内为细小密集的针状铁素体和少量珠光体;热影响区组织主要为先共析铁素体、针状铁素体、珠光体和少量的粒状贝氏体;母材为均匀细小分布的铁素体和珠光体。 展开更多
关键词 S355j2g3低合金钢 焊接接头 力学性能 显微组织
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S355J2G3钢疏松缺陷控制 被引量:2
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作者 郑辉 付宪强 谢奎龙 《特钢技术》 CAS 2013年第3期20-22,共3页
S355J2G3钢锻件低倍质量要求很严,通过提高钢水纯净度,改进绝热板质量,控制过热度、注速,以及锻造加热温度及保温时间等措施,大幅度降低了疏松缺陷的发生。
关键词 S355j2g3钢 锻件 疏松
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不同焊接顺序的汽车用S355J2G3钢工字梁焊接结构变形和残余应力的有限元预测 被引量:7
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作者 郭三爱 《热加工工艺》 CSCD 北大核心 2013年第9期192-195,共4页
基于焊接热弹塑性有限元分析理论,采用焊接专用有限元分析软件对不同焊接顺序的汽车用S355J2G3钢工字梁焊接结构手工MAG焊接过程进行了数值仿真,获得不同焊接顺序下焊接结构的变形和残余应力分布。模拟时,选择双椭球焊接热源模型,考虑... 基于焊接热弹塑性有限元分析理论,采用焊接专用有限元分析软件对不同焊接顺序的汽车用S355J2G3钢工字梁焊接结构手工MAG焊接过程进行了数值仿真,获得不同焊接顺序下焊接结构的变形和残余应力分布。模拟时,选择双椭球焊接热源模型,考虑了材料热物理性能与温度的非线性关系,以及相变潜热对温度场的影响。重点研究了焊缝及临近焊缝区域焊接残余应力和变形的分布特征,并进行了理论分析。 展开更多
关键词 S355j2g3钢 焊接变形 残余应力 有限元分析
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