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FAREY SEQUENCE OF NONLINEAR DIFFERENTIAL DYNAMIC SYSTEM IN TWO DIMENSIONS

H. Q. Jin and S. N. Xu Shenyang Institute of Technology , Shenyang 110015 , China

金属学报(英文版)

In this paper , through the discrim ination of Farey sequence in the forced Brusselator withweak coupling , it is proved that there is a topological translation fro m a nonlinear differen tial system ( limit cycle) to the circle m ap .

关键词: non - linearity , null , null , null

SPV50Q钢在含H2S酸性环境下的腐蚀特性

唐建群 , 巩建鸣 , 涂善东

中国腐蚀与防护学报

利用动电位极化和交流阻抗技术,研究了SPV50Q钢在含H2S酸性环境下的腐蚀特性。结果表明,H2S的存在对钢腐蚀过程影响很大,腐蚀速度随H2S浓度的增大而增大;随pH值的降低和溶液温度的升高,钢的腐蚀速度亦在不断增强;尽管随浸泡时间的延长,感抗弧半径不断增大,但其变化幅度不大,并在一定时间后减小,表明钢表面所形成的硫化物膜保护性较差,不能有效抑制钢的腐蚀。

关键词: 动电位极化 , EIS , SPV50Q steel , H2S

不同H2S分压下N80油管钢的CO2/H2S腐蚀行为

张清 , 李全安 , 文九巴 , 张兴渊

腐蚀与防护 doi:10.3969/j.issn.1005-748X.2008.03.008

采用高温高压釜试验,辅以失重法计算和扫描电镜分析,对不同H2S分压(O.0015 MPa,0.015 MPa,0.02MPa,0.06 MPa,0.12 MPa)下N80油管钢的CO2/H2S腐蚀行为进行了研究.结果表明,在试验H2S分压范围内,N80油管钢发生了极严重的CO2/H2S腐蚀;随着Hzs分压的升高,腐蚀速率先增加后降低,且在H2s分压为0.02 MPa时腐蚀速率取得最大值.

关键词: H2S分压 , N80钢 , C02/H2S腐蚀 , 腐蚀速率

亚稳态He(23S)原子与N2H4分子传能产物的发光研究

胡义华 , 刘美希 , 陈丽 , 王小涓 , 储焰南 , 曹德兆

量子电子学报 doi:10.3969/j.issn.1007-5461.2001.04.008

本文在流动余辉装置上,研究了亚稳态He(23S)原子与N2H4分子碰撞传能,观察到了激发态产物NH(A3II→X3∑+)、NH(c1II→a1△)、NH2(A2A1→X2B1)的发射光谱,由相对光谱强度求得了形成各产物的通道比;分析NH(A3II,v'=0)的转动分辨谱的结果表明,v'=0能级上的转动布居是"双模”分布,激发态产物NH(A)、NH2(A)的形成机理可能是: He(23S)+N2H4→N2H4*→NH(A)+NH2(A)+H.

关键词: 碰撞传能 , 化学发光 , NH(A3Ⅱ)的发射光谱

The effect of environmental variables on atmospheric corrosion of carbon steel in Shenyang

Chinese Science Bulletin

A study was carried out in order to investigate the effect of contaminants and meteorological variables on the rust layer of carbon steel exposed in Shenyang urban atmosphere. Seven kinds of contaminants and twelve kinds of meteorological parameters were also registered in order to correlate the data with respect to corrosion rate and the stepwise multiple regression analysis was carried out in order to obtain the best regression model. The sum of rainfall time as well as sunshine time and the concentration of H(2)S could stimulate initial atmospheric corrosion of carbon steel. The initial atmospheric corrosion kinetics of carbon steel was observed to follow the cubic equation. The corrosion products were analyzed by XRD and the transformation of phases in different periods was discussed.

关键词: contaminants;meteorological parameters;carbon steel;urban atmospheric;corrosion;stepwise multiple regression;corrosion products;rust;pollution

N80#油管钢在含H2S酸性溶液中的腐蚀行为

何晓英 , 李容 , 廖钫等

腐蚀学报(英文)

用稳态极化法、阳极动电位扫描法和交流阻抗法研究了酸性溶液中pH值和H2S的浓度 对N80#油管钢腐蚀行为的影响.结果表明:随着溶液pH值的减小、H2S浓度的增大N80#油 管钢的腐蚀速率加快;HAcNaAc体系中无H2S时,油管钢在活性溶解过程中生成的吸附性 中间产物是Fe(OH)ad,而加入H2S后,则生成了另一种吸附性中间产物—Fe(SH) ad.

关键词: 酸性溶液 , H2S , N80# oil pipe steel , corrosion

N80#油管钢在含H2S酸性溶液中的腐蚀行为

何晓英 , 李容 , 廖钫 , 李明齐 , 蔡铎昌

腐蚀学报(英文) doi:10.3969/j.issn.1002-6495.2001.04.015

用稳态极化法、阳极动电位扫描法和交流阻抗法研究了酸性溶液中pH值和H2S的浓度对N80#油管钢腐蚀行为的影响.结果表明:随着溶液pH值的减小、H2S浓度的增大N80#油管钢的腐蚀速率加快;HAc-NaAc体系中无H2S时,油管钢在活性溶解过程中生成的吸附性中间产物是Fe(OH)ad,而加入H2S后,则生成了另一种吸附性中间产物-Fe(SH)ad.

关键词: 酸性溶液 , H2S , N80#油管钢 , 腐蚀

First-principles study on the electronic structure and magnetic properties of metallic antiferromagnet C7H3S2N2

Journal of Magnetism and Magnetic Materials

First-principles full potential linearized augmented plane wave (FPLAPW) calculations have been performed to study the electronic structure and the magnetic properties of 3-Cyanobenzo-1,3,2-dithiazolyl,C7H3S2N2. The density of states (DOS), the total energy of the cell, and the spontaneous magnetic moment of C7H3S2N2 were all calculated. The calculations reveal that the low-temperature phase of the compound C7H3S2N2 has a stable metal-antiferromagnetic ground state, and there exists an antiferromagnetically coupled interactions between the dithiazolyl radical(1), which is in good agreement with experiment. (C) 2006 Elsevier B.V. All rights reserved.

关键词: first-principles;antiferromagnetic states;hybridization;organic;magnets;charge-transfer salts;temperature

RE-N-C-S-V-Nb多元共渗H13钢的热疲劳性能研究

徐永礼 , 庞祖高 , 马宽猷 , 韦曼云 , 黄银燕

表面技术

利用扫描电镜、X射线衍射分析技术,对比经过RE-N-C-S-V-Nb多元共渗处理、气体渗氮处理和淬火+回火处理的H13钢三种试样的热疲劳性能,依据裂纹特征、裂纹结构,证明RE-N-C-S-V-Nb多元共渗H13钢具有较强的抗热疲劳性能.研究了多元共渗钒铌碳氮化物的细晶强化作用和位错强化作用,及其对钢热稳定性、高温硬度和抗氧化性的影响,从理论上揭示了RE-N-C-S-V-Nb多元共渗对热疲劳性能的强化机制.

关键词: H13钢 , 多元共渗 , 热疲劳性 , 热稳定性 , 抗氧化性

RE-N-C-S-V-Nb多元共渗H13钢的高温耐磨性

徐永礼 , 覃海泉 , 庞祖高 , 徐宇 , 徐仁强 , 郑勇

表面技术 doi:10.16490/j.cnki.issn.1001-3660.2015.04.011

目的:研究RE-N-C-S-V-Nb多元共渗H13钢的高温耐磨性,为避免铝型材挤压模具的早期磨损失效提供表面强化的新工艺。方法把多元共渗试样及对比试样进行高温摩擦磨损实验,然后利用金相显微镜、扫描电镜、能谱分析仪、X射线衍射仪等设备进行检测分析。结果淬火试样和软氮化试样均存在较严重的磨粒磨损和粘着磨损现象,渗层有微裂纹,高温摩擦系数曲线有明显的波动和峰值,磨损率分别为21.20×10-13,11.30×10-13 m3/(N·m),在560℃保温4 h后的显微硬度分别为584,1018HV0.1。RE-N-C-S-V-Nb多元共渗试样以微量氧化磨损和微量粘着磨损形式出现,渗层无裂纹,高温摩擦系数曲线平缓,磨损率仅为2.96×10-13 m3/(N·m),显微硬度高达1334HV0.1。结论 RE-N-C-S-V-Nb多元共渗H13钢具有较强的高温耐磨性。

关键词: 多元共渗 , 高温耐磨性 , 摩擦系数 , 磨损率

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