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THERMAL FATIGUE AND FRACTURE MECHANICS ANALYSIS OF GREY CAST IRON

GUO Chengbi ZHOU Weisheng Dalian Institute of Technology , Dalian , Liaoning , China Professor , Dept.of Shipbuilding , Dalian Institute of Technology , Dalian , Liaoning , China

金属学报(英文版)

The in-phase and out-of-phase thermal fatigue,the C-P type and P-C type isothermal fa- tigue of grey cast iron were experimentally studied.The fatigue life was evaluated analytically by using the elastic-plastic fracture mechanics method(mainly J integral).The results of ex- periments and calculations showed that the lifes of in-phase and C-P type fatigue are longer than that of out-of-phase and P-C type fatigue respectively within the same strain range. This is in contrast to the results of other materials such as low carbon steel.On the other hand, the predicted lifes are consistent with experimental results.This suggests that J integral as a mechanics parameter for characterizing the thermal fatigue strength of grey cast iron and the mechanics model and the calculation method developed here are efficient.A parameter ΔW_1 was proposed from energy aspect to characterize the capacity of crack propagation. The isothermal fatigue life is the same as the thermal fatigue life for identical ΔW_1 values.

关键词: grey cast iron , null , null

DEPT135测定Resol的组成及微细结构参数

杨金瑞 , 余尚先 , 顾江楠

高分子材料科学与工程

通过对resol(羟甲基酚化合物和低分子量羟甲基酚树脂)DEPT135图谱的分析讨论,得到一系列计算resol微细结构参数的经验公式.根据DEPT135图谱可判断是否发生缩聚反应,根据经验公式可计算酚单体各个活性点参与反应百分率或酚羟基导入率、不同类型缩聚所占百分率及低分子量羟甲基酚树脂的平均核体数.

关键词: 羟甲基酚化合物 , 羟甲基酚树脂 , DEPT135 , 结构参数

Experimental study of inducing compressive stress by anti-welding heating treatment in a thin plate weldment with variant temperatures

材料科学技术(英文)

Significant compressive stress may be induced in thin plate weldment by anti-welding heating treatment (AWHT) with a temperature difference above 350degreesC, and an interesting phenomenon of obvious residual stress reduction on non-treated surface was discovered. The method of AWHT has no great effect on the mechanical properties including hardness, strength and toughness of the metal material. The results in the paper prompt a possibility application in shipbuilding industry.

关键词: experimental study;auti-welding heating treatment;thin plate weldment;welding residual stress

NUMERICAL ANALYSIS OF THREE-DIMENSIONAL FLUID FLOW AND HEAT TRANSFER IN TIG WELD POOL WITH FULL PENETRATION

WU Chuansong , CAO Zhenning , WU Lin Harbin Institute of Technology , Harbin , China

金属学报(英文版)

A model is established to analyze three-dimensional fluid flow and heat transfer in TICweld pools with full penetration.It considers the deformation of the molten pool surfaceat the condition of full penetrated workpieees,takes the are pressure as the drivingforce of the pool surface deformation,and determines the surface configuration of weldpool based on the dynamic balance of arc pressure,pool gravity and surface tension atdeformed weld pool surface. The SIMPLER algorithm is used to calculate the fluid flowfield and temperature distribution in TIG weld pools of stainless steel workpieces.TIGwelding experiments are made to verify the validity of the model.It shows the calculatedresults by the model are in good agreement with experimental measurements. professor,Dept of Welding Engineering,Harbin Institute of Technology,Harbin 150006,China

关键词: KEY WORDS TIG weld pool , null , null , null , null

蓖麻油和聚氧乙基蓖麻油的结构和组成的波谱表征

张蓉 , 靳焜 , 彭勤纪 , 张华

应用化学 doi:10.3969/j.issn.1000-0518.2002.04.017

用核磁共振波谱、质谱和红外光谱表征了蓖麻油和非离子表面活性剂聚氧乙基蓖麻油的结构特征和它们的组成.用带梯度场的氢同核相关谱(gCOPY)、带梯度场的氢检测异构单量子相关谱(gHSQC)、带梯度场的氢检测异核远程相关谱(gHMBC)和无畸变的极化转移增强法(DEPT)对核磁谱带进行归属.结果表明,聚氧乙基蓖麻油至少由6个系列化合物组成.

关键词: 核磁共振波谱法 , 质谱法 , 红外光谱法 , 蓖麻油 , 聚氧乙基蓖麻油

植物纤维多羟基醇的液化机理

陈秋玲 , 谷俊杰 , 孙可伟 , 张春红 , 田森林

高分子材料科学与工程

采用有机溶剂萃取和柱层析相结合的方法,从麦秆液化混合液中,除得到大量降解多糖外,经分离提纯得到两种关键组分.利用核磁(1 H-NMR,13C-NMR,DEPT)、质谱(MS)和红外(IR)等方法,分析得出产物1是乙酰丙酸聚乙二醇酯,产物2含有2分子苯环,是含有愈创木基木质素和对羟基苯基木质素结构单元的酯类化合物.通过产物的波谱数据分析其结构,并结合液化过程中酸值、羟值及残渣的变化,推导出植物纤维中木质素和纤维素液化的反应机理.

关键词: 纤维素 , 木质素 , 液化 , 机理

南海红树林内源真菌#2240的3个蒽醌类次级代谢产物的鉴别和药理活性

谭倪 , 邵长伦 , 陶李明 , 何丽仙 , 佘志刚 , 林永成

应用化学 doi:10.3969/j.issn.1000-0518.2009.03.007

通过人工发酵培养,利用层析技术,从南海红树林内源真菌#2240的培养液中分离得到3个蒽醌类次级代谢产物,它们分别是:(+)-3,3',7,7',8,8'-六羟基-5,5'-二甲基连二蒽醌(化合物1),1,4,5-三羟基-7-甲基蒽醌(化合物2)和1,6,8-三羟基-3-甲基蒽醌(化合物3),其中化合物1为新化合物. 它们的结构通过谱图分析(包括1H、13C NMR、DEPT、HMQC、HMBC、HREIMS、UV-Vis及IR等)和相关文献得以确定. 初步药理实验表明,化合物1对DNA拓扑异构酶(hTopo I)具有强抑制活性,最低抑制浓度2.35×10-4 mol/L,结果远低于阳性对照物喜树碱之值1.00×10-3 mol/L.

关键词: 红树林内源真菌 , 蒽醌 , 次级代谢产物 , DNA拓扑异构酶 , 抑制活性

马来酰己二胺酸改性聚乳酸的合成与表征

钱智勇 , 罗彦凤 , 傅亚 , 张徭尧 , 霍润兰 , 王远亮

功能材料

以马来酸酐和己二胺为原料制备出了一种新型的马来酰己二胺酸单体(HOOC-MAH-HDA-NH2),然后采用自由基熔融接枝技术将HOOC-MAH-HDA-NH2引入到PDLLA骨架中,形成了结构与己二胺改性聚乳酸(HMPDLLA)相似的MHP-DLLA材料。采用红外光谱(FT-IR)、核磁共振氢谱(1 H NMR)、核磁共振碳谱(13 C NMR)和DEPT 135对HOOC-MAH-HDA-NH2和MHPDLLA的化学结构进行了定性和定量表征。以PDLLA为空白,HMP-DLLA为对照,对MHPDLLA的分子量进行了测定。结果表明采用新的合成工艺使聚合物的分子量从原有的66%~68%降低到了33%~34%,且合成路线更简单。在合成路线和合成工艺上的创新为MHPDLLA用作生物活性材料或仿生材料的基质材料开辟了更广阔的空间。

关键词: 聚(DL-乳酸) , 自由基接枝共聚 , 马来酰己二胺酸

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