N. Li 1)
,
Y.H. Wen 1)
,
Y.G. Xu 1)
,
M.J. Tu 1)
,
P.Q. Li 2)
,
Y.L. Liu 2) and Y.L.Ma 2) 1) Department of Materials Shaping and Controlling Engineering
,
Sichuan University
,
Chengdu 610065
,
China 2) Xi'an Petroleum Pipe Research Institute
,
Xi'an 710065
,
China
金属学报(英文版)
The effect of quenching temperature on the recovery stress of Fe 18Mn 5Si 8Cr 4Ni shape memory alloy has been studied. The results show that both the maximum recovery stress σ h in heating and the recovery stress σ c at room temperature after heating increased as increasing quenching temperature increased, both σ h and σ c reached maximum at 650℃, and then decreased rapidly with the further increase in quenching temperature,but the descent degree of σ c was far bigger than that of σ h; When the quenching temperature is higher than 850℃, the further increase in quenching temperature had little effect on them; At random quenching temperature, σ c was far bigger than σ h.
关键词:
shape memory alloy
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null
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null
刘国华
,
杨平
,
蒋宛莉
,
郭晓稚
,
许贵宝
,
蒋雪璋
,
沈梁
,
王筱梅
功能材料
选择氮杂芴(咔唑)为π-中心,分别以三苯胺和噁二唑取代基为"枝",合成了两个强双光子吸收的氮杂芴衍生物-2,8-双(4-三苯胺乙烯基)-N-乙基氮杂芴(简称NT-G1)和2,8-双(2-(4'-乙氧基)-5-(4'-苯乙烯)-1,3,4- 噁二唑)-N-基氮杂芴(简称NO-G1),进行了核磁共振谱和质谱等表征.飞秒钛宝石激光器泵浦下,NT-G1和NO-G1溶液发出强双光子上转换荧光,且后者的双光子荧光发射截面是前者的7倍;双光子荧光法计算出NT-G1和NO-G1双光子吸收截面分别为215GM和454GM.分子构型优化表明,NT-G1分子中心"氮杂芴"所在平面与两端苯环呈螺旋桨式排布;而NO-G1分子共轭长度增大,且中心的"氮杂芴"与两端延伸的"枝"呈平面构型;从结构上看,NO-G1分子属"D-A-π-A-D"型,具有明显的pn结模式,这些都使NO-G1分子具有更好的分子内电荷转移能力,因而有较高的双光子吸收截面.
关键词:
2,8-双(4-三苯胺乙烯基)氮杂芴
,
2,8-双(2-(4'-乙氧基)-5-(4'-苯乙烯)-1,3,4- 噁二唑)-N-乙基氮杂芴
,
双光子吸收
,
双光子荧光
Journal of Superconductivity and Novel Magnetism
The local structure and the g factors (g(x), g(y), and g(z)) of the Cu(2+) site in Y(2)BaCuO(5) are theoretically studied using the perturbation formulas of the g factors for a 3d(9) ion in orthorhombically elongated octahedra. The orthorhombic field parameters in these formulas are determined from the superposition model and the local geometry of the system. From the calculations, the oxygen octahedron is found to undergo the local elongation Delta Z (approximate to 0.05 angstrom) along c-axis and the relative bond length variation Delta X (approximate to 0.1 angstrom) along a- and b-axes, respectively. The calculated g factors based on the above local structure are in good agreement with the experimental data. The relationships between the anisotropies of the g factors and the low symmetrical (orthorhombic) distortions of the Cu(2+) site in Y(2)BaCuO(5) are discussed.
关键词:
Crystal fields and spin Hamiltonians;Electron paramagnetic resonance;Cu(2+);Y(2)BaCuO(5);crystal
于萍
,
王亚权
腐蚀学报（英文）
研究了添加0.1mass%稀土Y的铸造K38G高温合金在1000℃的恒温氧化行为.结果表明,较之不含Y的合金，含Y铸态K38G合金的氧化速率显著降低； 氧化时形成双层的外氧化膜，表层为以Cr2O3和TiO.2为主的混合氧化物层，内层为连续的Al2O3层；没有内氧化和内氮化，没有氧化膜的剥落，加入稀土Y有效地提高了氧化膜的粘附性能.
关键词:
高温氧化
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null
,
null
,
null
于萍
,
王亚权
腐蚀学报（英文）
doi:10.3969/j.issn.1002-6495.2007.03.010
研究了添加0.1 mass%稀土Y的铸造K38G高温合金在1000℃的恒温氧化行为.结果表明,较之不含Y的合金,含Y铸态K38G合金的氧化速率显著降低;氧化时形成双层的外氧化膜,表层为以Cr2O3和TiO2为主的混合氧化物层,内层为连续的Al2O3层;没有内氧化和内氮化,没有氧化膜的剥落,加入稀土Y有效地提高了氧化膜的粘附性能.
关键词:
高温氧化
,
K38G
,
高温合金
,
稀土元素
,
Y
于萍
,
王亚权
,
王文
腐蚀学报（英文）
对加入0.05mass%～0.5mass%稀土Y铸造的K38G高温合金800 ℃恒温的氧化行为进行了研究.结果表明,含Y铸态K38G合金的氧化动力学曲线偏离了抛物线规律，接近于立方规律；Y有效抑制了该合金的内氧化；当Y含量达0.5mass%时，该合金中析出富Y相，降低了其氧化抗力.
关键词:
高温氧化
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null
,
null
Applied Physics Letters
The effect of nonmagnetic Y partial substitution at the Dy site in Dy(1-x)Y(x)MnO(3) up to x=0.2 on magnetism, specific heat, and ferroelectricity is investigated, which resulted in a preliminary multiferroic phase diagram. It is revealed that the Y partial substitution suppresses the Dy-spin ordering point (T(Dy)) and ferroelectric ordering point (T(FE)) but enhances the Mn-spin ordering point (T(N)). The interaction between the spins of Dy and Mn is remarkably affected by Y substitution. The measured electrical polarization depends on the Y substitution in a complex way because the ferroelectricity is sensitive to the interaction between the spins of Dy and Mn. (c) 2011 American Institute of Physics. [doi: 10.1063/1.3536506]
关键词:
ferroelectricity;polarization
