彭加瑜
,
SANDRA Pat
色谱
doi:10.3321/j.issn:1000-8713.2004.03.024
将多糖胶的混合物与荧光剂9-氨基芘-1,4,6-三磺酸(APTS)派生后再进行微量离心过滤分离.所得到的高分子部分采用毛细管电泳(CE)分离和激光诱导荧光(LIF)检测技术进行分析.缓冲溶液pH的调节和聚丙烯酰胺(PAA)涂层毛细管的使用有效地改善了多糖胶的分离效率和峰形.在优化条件下,iota、kappa角叉菜胶、藻胶、xanthan、carboxymethyl cellulose (CMC)等5种组分的混合物和阿拉伯树胶、刺梧桐树胶、CMC等3种组分的混合物分别在pH 3.2和7.8的缓冲溶液下得到了完整组分的分离.这被认为是一种分析多糖胶的既简单快速又有效的方法.
关键词:
毛细管电泳
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激光诱导荧光
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聚丙烯酰胺涂层毛细管
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多糖胶
材料科学技术（英文）
The NiAl phase prepared by pack cementation (PC) on a nickel base superalloy was investigated by X-ray photoelectron spectroscopy (XPS) and positron annihilation technique (PAT). The focus was on the effect of the solid solution of the alloying element from substrate on the binding energy of Ni (Al) 2p peaks and vacancy concentration of the NiAl phase formed in a superalloy. The results showed that the binding energy of Ni 2p peak of the NiAl phase grown in a superalloy was shifted by up-to 0.55 eV at the temperature from 850 to 1050 degrees C towards higher energies and the binding energy of Al 2p peak by up to 1.09 eV in comparison with the NiAl phase formed in pure Ni. The positron lifetimes obtained from the NiAl phase formed in a superalloy were found to be markedly lower than the theoretical values, indicating the decrease in vacancy concentration. The variation of binding energies and, vacancy concentration are possibly due to the solid solution of the alloying atoms from the substrate into the NiAl lattice.
关键词:
NiAl phase;Ni-base superalloy;positron annihilation technique (PAT);X-ray photoelectron spectroscopy (XPS);intermetallic compounds;electronic-structure;positron-lifetime;aluminides
Hua WEI
材料科学技术（英文）
The NiAl phase prepared by pack cementation (PC) on a nickel base superalloy was investigated by X-ray photoelectron spectroscopy (XPS) and positron annihilation technique (PAT). The focus was on the effect of the solid solution of the alloying element from substrate on the binding energy of Ni (Al) 2p peaks and vacancy concentration of the NiAl phase formed in a superalloy. The results showed that the binding energy of Ni 2p peak of the NiAl phase grown in a superalloy was shifted by up to 0.55 eV at the temperature from 850 to 1050℃ towards higher energies and the binding energy of Al 2p peak by up to 1.09 eV in comparison with the NiAl phase formed in pure Ni. The positron lifetimes obtained from the NiAl phase formed in a superalloy were found to be markedly lower than the theoretical values, indicating the decrease in vacancy concentration. The variation of binding energies and vacancy concentration are possibly due to the solid solution of the alloying atoms from the substrate into the NiAl lattice.
关键词:
NiAl phase
,
null
,
null
冯宏剑
,
赵杰
功能材料
用IBAD(ion beam assisted deposition)方法镀TiN膜不但有很好的膜基结合力,而且纳米硬度、耐腐、耐磨性能可通过高低能结合的方法来提高.本文作者用PAT(positron annihilation technique)技术分析了在同一高低能条件下不同参数对Si基底的缺陷的影响,解释并论证了改进实验的方法.
关键词:
IBAD
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PAT
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缺陷
Jingcheng WANG
,
Fuqiang YOU
,
Junlin YIN
,
Guohua GAO
材料科学技术（英文）
An amorphous alloy with Ni-(17 similar to 19) at. pct P prepared by electrodeposition process was studied using positron annihilation technique (PAT) associated with X-ray diffraction and the measurement of corrosion rate. It is suggested that defect or the interface between precipitates and matrix is one of the important factors which decrease corrosion resistance of the alloy after crystallization.
关键词:
