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A SRUDY ON CORROSION RESISTANCE OF DIFFERENT MATERIAL IN CONDENSATE WATER FROM A NATURAL GAS PURIFYING STATION

Y.Z. Luo , D.Y. Yu , Z.M. Xu , Y. Luo , G.T. Qi and J.L. Yang Departent of Chemistry , Huazhong University of Science and Technology , Wuhan 430074 , China

金属学报(英文版)

The corrosion behaviors of different material in the condensate water from the natural gas purifying station were studied by laboratory tests, field tests and measurements of polarization curve. The results showed that hot dipping aluminum steel had a good corrosion resistance to the accompanying gas of crude oil and condensate water in the natural gas purifying station.

关键词: condencate water , null , null

Mean-field theory on mixed ferro-ferrimagnetic compounds with (A(a)B(b)C(c))(y)D

Physics Letters A

The magnetic properties of the mixed ferro-ferrimagnetic compounds with (A(a)B(b)C(c))(y)D, in which A, B, C and D are four different magnetic ions and form four different sublattices, are studied by using the Ising model. And the Ising model was dealt with standard mean-field approximation. The regions of concentration in which two compensation points or one compensation point exit are given in c-a, b-c and a-b planes. The phase diagrams of the transition temperature T-c and compensation temperature T-comp are obtained. The temperature dependences of the magnetization are also investigated. Some of the result can be used to explain the experimental work of the molecule-based ferro-ferrimagnet ((NiaMnbFecII)-Mn-II-Fe-II)(1.5) [Cr-III (CN)6] - zH(2)O. (C) 2003 Elsevier B.V. All rights reserved.

关键词: mixed ferro-ferrimagnet;Ising model;four sublattices;phase diagram;transition temperature;compensation temperature;magnetic-properties;prussian blue;alloy

Electrochemical noise analysis on the pit corrosion susceptibility of Mg-10Gd-2Y-0.5Zr, AZ91D alloy and pure magnesium using stochastic model

Corrosion Science

Pit corrosion susceptibilities of Mg-10Gd-2Y-0.5Zr alloy, AZ91D alloy and pure magnesium were investigated by means of electrochemical noise (EN). The EN data have been analyzed based upon the combined stochastic theory and shot-noise theory. Pit initiation process has been modeled as a nonhomogeneous Poisson process and analyzed using a Weibull distribution function. Pit growth process has been simulated by a nonhomogeneous Markov process and analyzed using Gumbel distribution function. The EN results implied that Mg-10Gd-2Y-0.5Zr alloy had the highest pit initiation rate and pit growth probability, which revealed that Mg-10Gd-2Y-0.5zr alloy had the highest pit susceptibility. (C) 2008 Elsevier Ltd. All rights reserved.

关键词: Magnesium;Rare earth elements;Electrochemical calculation;Pitting;corrosion;pitting corrosion;neutral chloride;aluminum-alloys;initiation;growth;parameters;behaviors;phosphate;kinetics;sulfate

Energy levels of the d*(8) electron and d*(2) hole system

Physical Review B

In the investigation of the optical and magnetic properties of the semiconductors containing transition-metal ions, the one-electron orbital cannot be treated with a pure d orbital because of a strong covalence. This paper presents the energy matrix of the d*(8) and d*(2) (d* means a modified d function) system, in which the covalence is described by two covalent factors. The differences between the matrix diagonal elements of the t(2)(m)e(n) term of the d*(8) system and the t(2)(6-m)e(4-n) term of the d*(2) system vary with m and n. The d(N) electron system can be explained with the d(10-N) hole system because the difference between the energy matrix of the d(N) and d(10-N) systems has a fixed value. However, this kind of simple relation does not exist for the d*(N) and d*(10-N) systems when the covalence is considered. A numerical calculation shows that the variation of the energy levels with the covalence for Ni2+ in the d*(8) electron system is larger than that in the d*(2) hole system. The calculated energy levels obtained from the d*(8) matrix are in good agreement with the experimental data of the Ni2+ ion for ZnS:Ni and ZnSe:Ni. This suggests that the d*(8) electron system instead of the d*(2) hole system should be used in the investigation of optical and magnetic properties of semiconductor containing Ni2+ ions.

关键词: zns-ni;absorption;vanadium;impurities;spectra;ions

钇对AZ91D镁合金组织和力学性能的影响

齐伟光 , 赵宝荣 , 许小忠 , 刘常明

兵器材料科学与工程 doi:10.3969/j.issn.1004-244X.2007.02.014

研究在通氩气下Y精炼剂对AZ91D镁合金组织和性能的影响.试验结果表明,AZ91D镁合金加入Y后,显微组织主要由α-Mg基体相、β相(Mg17Al12)、Al2Y相和Al6Mn6Y相组成.经复合净化处理后的AZ91D镁合金力学性能明显改善,平均抗拉强度由101.88 MPa提高到141.91 MPa,但延伸率提高不明显.

关键词: AZ91D镁合金 , , 显微组织 , 力学性能

铈、钇在AZ91D镁合金中的存在形式及其作用

郭锋 , 李鹏飞 , 高霞 , 许娟

中国稀土学报

在AZ91D镁合金中添加稀土元素Ce和Y,研究了Ce,Y元素在铸态AZ91D镁合金中的存在形式以及对合金组织和性能的影响.结果表明,铸态AZ91D镁合金中加入的Ce,Y大部分形成Al4Ce和Al2Y化合物,少量剩余的Ce,Y部分取代Mg元素的位置,以代位固溶的形式固溶在α-Mg固溶体和β-Mg17Al12金属间化合物中;Ce,Y能够细化镁合金铸态组织的晶粒,使Mg17Al12相发生"断网"并减少其在组织中的相对比例;适量添加Ce,Y能够提高AZ91D镁合金铸态机械性能,其主要原因是Ce,Y的细晶作用、固溶强化作用、Al-RE相的第二相强化作用以及对Mg17Al12相强化作用的改善.

关键词: 稀土铈和钇 , AZ91D镁合金 , 存在形式 , 组织性能

Optical spectra and spin Hamiltonian parameters for rhombic Zr3+ in Y3Al5O12

Journal of Applied Physics

The four optical spectrum bands (or d-d transitions) and six spin Hamiltonian parameters (g factors g(x), g(y), g(z) and hyperfine structure constants A(x), A(y), A(z)) of the rhombic Zr3+ (4d(1)) center in Y3Al5O12 crystal are calculated from the complete diagonalization (of energy matrix) method and the perturbation theory method. The calculated results from both methods are not only close to each other but also in good agreement with the experimental values. It appears that the two microscopic theory methods (which are very close to those used in a 3d(1) system) are effective in the explanations of the optical and electron paramagnetic resonance spectra for a 4d(1) system. From the calculations, the optical spectrum bands are reassigned and the defect structure of the rhombic Zr3+ center in Y3Al5O12 crystal is estimated. (c) 2007 American Institute of Physics.

关键词: electron-paramagnetic-res;crystal fields;epr;ions;linewidth

稀土钇对AZ91D镁合金微观组织和腐蚀性能影响的研究

齐伟光 , 王进华 , 邢志媛 , 吕绯 , 刘环恩 , 李冬梅

兵器材料科学与工程 doi:10.3969/j.issn.1004-244X.2009.04.022

为改善镁合金的耐腐蚀性能,进一步拓宽镁合金的应用范围,研究通氩气下加入稀土Y对AZ91D镁合金组织和性能的影响.结果表明:AZ91D镁合金加入Y后,显微组织主要由α-Mg基体相、β相(Mg_(17)Al_(12))、Al_2Y相和Al_6Mn_6Y相组成.加入1%Y能显著降低合金的腐蚀速度,提高合金的平衡电位和腐蚀电位,降低腐蚀电流.

关键词: 镁合金 , 显微组织 , 腐蚀性能

液晶材料与3D显示

张兴 , 郑成武 , 李宁 , 周兴丹 , 李正强 , 华瑞茂

液晶与显示 doi:10.3788/YJYXS20122704.0448

介绍了3D显示的基本原理,重点介绍了目前3D显示的主流技术类型,包含了眼镜式3D技术以及裸眼式3D技术,其中眼镜式3D技术包含色差式3D技术、偏光式3D技术和主动快门式3D技术;裸眼式3D技术包含视差屏障式3D技术、柱状透镜式3D技术、指向光源式3D技术和多层显示式3D技术.阐述了各种3D显示技术的基本实现原理和应用领域、并对涉及液晶显示的几种3D技术的优缺点进行了对比.结合液晶材料的特点与3D液晶显示的实际要求,阐述了3D液晶面板对液晶材料快速响应方面的要求,以及液晶透镜对液晶材料光学各向异性参数的要求.

关键词: 3D显示 , 眼镜式3D显示 , 裸眼式3D显示 , 液晶材料

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