S.P. Mondal
材料科学技术(英文)
The magnetic and structural properties of FINEMET alloy with a composition of Fe75.5Cu1Nb1Si13.5B9 were investigated after primary and secondary crystallization of amorphous ribbon sample. The crystallization behavior and the nanocrystal formation of the samples were performed by differential thermal analysis (DTA) which in turn was supported by X-ray diffraction (XRD) study. Temperature dependence of initial permeability of amorphous and devitri¯ed toroid shaped samples has been measured. Enhancement of Curie temperature of the amorphous alloy has been observed due to the irreversible structural relaxation. With the appearance of nanocrystalline phase the Curie temperature of the residual amorphous phase gradually decrease with the increase of annealing temperature. Their temperature dependence reflects the characteristic annealing temperature evolution of the basic magnetic parameters in these nanocrystalline systems. Saturation magnetization, Ms, increases with annealing temperature Ta for the samples and finally decreases during annealing at a temperature much higher than peak crystallization temperature.
关键词:
Nanostuctured alloy
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null
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null
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null
马保国
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许婵娟
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钟开红
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蹇守卫
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李相国
材料科学与工程学报
doi:10.3969/j.issn.1673-2812.2005.04.006
本文系统地研究了F、S、P元素对水泥熟料矿物形成过程和组成的影响及其叠加矿化效应,并通过化学分析和XRD分析探讨了其作用机理.研究结果表明:F、S、P元素在水泥烧成中均可降低液相出现和C3S形成温度,改善易烧性,但F、S叠加矿化效果最好,而且可以改善熟料的矿物组成及性能,避免了单掺F造成的熟料活性降低等问题.
关键词:
矿化效应
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氟石膏
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磷石膏
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易烧性
余庚华
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仲嘉琪
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王谨
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詹明生
量子电子学报
doi:10.3969/j.issn.1007-5461.2012.03.001
Ba原子是光频标的候选者之一,对其进行有效的激光冷却与囚禁需要相关能级的寿命和跃迁几率的信息.Ba原子激发态6s6p3P1能级在激光冷却实验中很重要,通过Hanle效应实验测量了这一能级的寿命和自发辐射率,从理论和实验上研究了探测激光有限线宽和光强对Ba原子基态6s21S0与激发态6s6p3P1之间跃迁(波长791nm)Hanle效应荧光信号的影响.在考虑了激光线宽和光强因素后所得到的激发态6s6p3P1的能级寿命和自发辐射率与其他方法给出的结果符合很好.
关键词:
光谱学
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能级寿命
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Hanle效应
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线宽
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Ba原子
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原子频标
材料科学技术(英文)
The doping of phosphorus, sulfur and boron in IN718 superalloy can remarkably influence the creep behavior. The modifications of the minor elements seem not to vary the stress exponent and the influences primarily concentrate on the effective diffusion coefficient. A pronounced beneficial interaction between P and B and a weaker detrimental interaction between P and S have been obtained. The preexponential frequency constant is proved to be strongly related with the creep activation energy because of the so-called compensation effect. The compensation temperature has been determined to be about 1080 K, which corresponds to the transformation temperature from rapidly coarsened gamma " phase to delta phase. It has been proposed that trace elements can influence the effective diffusion coefficient individually or cooperatively, which in turn either retard or speed the creep process.
关键词:
Z.Q. Hu
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W.R.Sun and S.R. Guo(Institute of Metal Research
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Chinese Academy of Sciences
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Shenyang 110015
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China Manuscript received 26 August 1996)
金属学报(英文版)
The effects of the trace elements, P, S and Si,on the solidification, segregation,microstructure and mechanical properties of GH761 and In718 alloys were studied.It was found that the segregation of the P,S and Si can be greatly aggravated or relieved by the precipitation taking place during the solidification. In the heat treated state,P enhances the intergranular precipitation in the GH761 alloy.The refinement of P in In718 alloy causes the appearance of a film-like δphase.Si increases the intergranular precipitation of the M_6C and the Laves Phase in the In718 alloy.P, S and Si play diverse roles in the tensile and the stress rupture properties of the GH761 and In718 alloys. The most striking effect is that P significantly prolongs the stress rupture lives of the GH761 and In718 alloys in a wide range of 0.00050.015 wt% .The mechanisms by which P,S and Si influence the superalloys are discussed in the text.
关键词:
: superalloy
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null
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null
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null
王建生
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韩其勇
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魏寿昆
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宋波
金属学报
应用Ba蒸气平衡法,在密封Mo反应室内,用自制的TiN和BaS坩埚,进行了纯Fe液中Ba—O,Ba—S,Ba—P平衡的研究。得到反应:BaO_(s)=[Ba]+[O]的标准自由能ΔG°_(wt-%)=188500+38.3T J/mol,e_O~(Ba)=624-1.25×10~6/TBaS_(S)=[Ba]+[S]的标准自由能ΔG°_(wt-%)=469100-111T J/mol,e_S~(Ba)=826-1.64×10~6/T1873K下,反应Ba_3P_2=3[Ba]+2[P]的K_(Ba_3P_2)=7.76×10~(-18),e_(Ba)~P=0.95,ΔG°_(wt-%)=613200 J/mol。
关键词:
Ba
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O
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S
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P
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liquid iron
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thermodynamic parameters
谭金枚
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王琪
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王雪力
高分子材料科学与工程
采用超声辐照乳液聚合得到聚(苯乙烯-苯乙烯磺酸钠)(P(S-SS))乳胶粒,用直接沉淀法在乳胶粒表面原位生成硫化镉(CdS)纳米粒子,得到P(S-SS)/CdS核壳粒子.用元素分析和XPS研究了共聚物的组成及磺酸基(-SO3-)的分布,结果表明,-SO3-主要分布在乳胶粒表面,有利于CdS纳米粒子在乳胶粒表面的沉积.用XRD、TEM及UV-vis表征了共聚物乳胶粒及P(S-SS)/CdS核壳粒子的结构及CdS的量子效应.结果表明,所制备的CdS纳米粒子为六方晶型,平均粒径为6 nm,在P(S-SS)乳胶粒外层形成多层包覆,P(S-SS)/CdS核壳粒子平均粒径为70 nm,CdS纳米粒子表现出明显的量子尺寸效应.
关键词:
P(S-SS)/CdS
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核壳粒子
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超声辐照
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乳液聚合
张雅妮
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罗金恒
材料保护
为了持续研究油套管钢的腐蚀磨损行为,揭示其腐蚀磨损机理,采用失重法和电化学法测试了油套管钢P110S在不同浓度氯化钠溶液中的腐蚀磨损行为.结果表明:对以索氏体和贝氏体为基本组织的油套管钢P110S而言,在不同浓度的氯化钠溶液中,腐蚀与磨损呈正交互作用;在所测试的3种浓度(0.01,0.10,1.00mol/L)中,P110S在0.10 mol/L氯化钠溶液中的失重最大;电化学研究显示,腐蚀磨损前随着氯化钠溶液浓度的增加,P110S的自腐蚀电位逐渐降低,在3种浓度氯化钠溶液中腐蚀磨损一定时间后,P110S的自腐蚀电位基本相同;P110S在0.01 mol/L和1.00 mol/L氯化钠溶液中的腐蚀磨损形貌呈现零散的鹅卵形冲击坑,坑底部存在着严重的塑性变形和局部断裂,而在0.10 mol/L的氯化钠溶液中,小的冲击坑遍布试样表面,坑密且浅.
关键词:
P110S
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腐蚀磨损
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氯化钠溶液
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失重法
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电化学法