材料期刊网

BP Neural Network of Continuous Casting Technological Parameters and Secondary Dendrite Arm Spacing of Spring Steel

JIANG Li-hong , WANG Ai-guo , TIAN Nai-yuan , ZHANG Wei-cun4 , FAN Qiao-li4

钢铁研究学报(英文版)

The continuous casting technological parameters have a great influence on the secondary dendrite arm spacing of the slab, which determines the segregation behavior of materials. Therefore, the identification of technological parameters of continuous casting process directly impacts the property of slab. The relationships between continuous casting technological parameters and cooling rate of slab for spring steel were built using BP neural network model, based on which, the relevant secondary dendrite arm spacing was calculated. The simulation calculation was also carried out using the industrial data. The simulation results show that compared with that of the traditional method, the absolute error of calculation result obtained with BP neural network model reduced from 0.015 to 0.0005, and the relative error reduced from 6.76% to 0.22%. BP neural network model had a more precise accuracy in the optimization of continuous casting technological parameters.

关键词: continuous casting , technological parameter , secondary dendrite arm spacing , BP neural network

Studies on the spin-Hamiltonian parameters of CuN(6) clusters and their tetragonal distortions due to Jahn-Teller effect for Cu(2+) in trigonal M(1-propyltetrazole)(6)(BF(4))(2) (M = Zn, Fe) crystals

Spectrochimica Acta Part a-Molecular and Biomolecular Spectroscopy

This paper reports the theoretical calculations for the anisotropic and isotropic spin-Hamiltonian parameters (g factors and the hyperfine structure constants) of tetragonal CuN(6) octahedral clusters due, respectively, to the static and dynamic Jahn-Teller effects for Cu(2+) ion in the trigonal M(=Zn, Fe) sites of M(1-propyltetrazole)(6)(BF(4))(2) crystals. The calculations are carried out using the high-order perturbation formulas based on a two-mechanism model, in which besides the contributions to spin-Hamiltonian parameters due to the crystal-field mechanism concerning the crystal-field excited states in the extensively used crystal-field theory, the contributions due to charge-transfer mechanism concerning the charge-transfer excited states (which are neglected in the crystal-field theory) are included. The calculated results are in reasonable agreement with the experimental values. From the calculations the tetragonal elongations Delta R= R(parallel to) R(perpendicular to) (where R(parallel to) and R(perpendicular to) denote the Cu-N distances parallel with and perpendicular to the C(4) axis) of CuN(6) octahedral clusters due to Jahn-Teller effect are obtained. The results are discussed. (C) 2010 Elsevier B.V. All rights reserved.

关键词: Electron paramagnetic resonance;Crystal- and ligand-field theory;Jahn-Teller effect;M(1-propyltetrazole)(6)(BF(4))(2) (M = Zn, Fe);Cu(2+);atomic screening constants;electron-paramagnetic-res;single-crystal;sulfate hexahydrate;charge-transfer;scf functions;epr;ions;field;copper(ii)

Jian ZHANG/Langhong Lou

材料科学技术（英文）

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Van Hove奇异性、非电声作用与HgBa2Cun-1CunO2n+2+δ(n=1,2,3)系统的超导电性

张霞 , 苏希玉 , 侯芹英 , 侯艳丽

低温物理学报 doi:10.3969/j.issn.1000-3258.2008.03.011

考虑态密度的Van Hove奇异性和非电声作用,我们在BCS理论框架内研究了HgBa2Cun-1CunO2n+2+δ(n=1,2,3)系统的超导转变温度和同位素效应.结果表明,当同时考虑Van Hove奇异性和非电声作用时,可以更好地解释HgBa2Cun-1CunO2n+2+δ(n=1,2,3)系统的超导性质.

关键词: Van Hove奇异性 , 非电声作用 , 超导转变温度 , 同位素效应

Congratulations to Prof. Dr. WEI Shoukun's 100th Birthday

金属学报(英文版)

关键词:

Dedicated to Prof. Dr. WEI Shoukun's 100th birthday

稀有金属（英文版）

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Mn4N固相合成反钙钛矿型Mn3MN(M:Cu, Ge)的机理研究

张从阳 , 朱洁 , 张茂才 , 周丽洁 , 汪洁

人工晶体学报

以Mn4N、Cu和Ge粉末为原料,在N2气氛下固相烧结合成了反钙钛矿结构的锰基氮化物Mn3MN(M:Cu, Ge).利用热重-差热分析(TG-DSC),X射线衍射(XRD),扫描电镜(SEM)等技术研究了合成Mn3MN(M:Cu, Ge)的固相反应机理及制备的工艺条件.固相反应的主要机理是Cu(或Ge)原子通过固溶扩散置换出Mn4N立方结构中顶点的Mn原子形成反钙钛矿结构;置换出来的Mn与多余的Cu反应形成Mn3Cu固溶相, 在N2气氛中氮化再次生成反钙钛矿Mn3CuN相.以Mn4N制备纯的反钙钛矿结构的Mn3MN需要严格控制原料的配比,且需要在高真空高纯N2保护气氛中进行烧结.

关键词: 固相反应 , 反钙钛矿结构 , 热重-差热分析

4,4 ',6,6 '-四叔丁基-2,2 '-[乙二氧双(氮次甲基)]二酚铜(Ⅱ)化合物的合成、结构及抑菌活性

冯建华 , 吴刚

应用化学 doi:10.11944/j.issn.1000-0518.2015.05.140287

在室温、无水乙醇溶剂中,H2L(H2L =4,4',6,6'-四叔丁基-2,2'-[乙二氧双(氮次甲基)]二酚)与一水合醋酸铜反应得到了一种新的铜(Ⅱ)化合物C32H46CuN2O4([CuL]),并通过红外光谱、元素分析及X射线单晶衍射等技术手段对[CuL]进行了表征.[CuL]的结构解析表明,属单斜晶系,空间群C2/c,晶胞参数为a=2.7231(3) nm,b=1.1196(3) nm,c=1.0704(2) nm,α=90.00°,β=101.293(2)°,γ=90.00°,V=3.2002(11) nm3,Z=4,Mr=586.25,Dc=1.217∥co,μ=0.718 mm-1,F(000)=1252,R1 =0.0957,wR2 =0.2297.[CuL]的对称单元中含有1个Cu(Ⅱ)原子和1个配位L分子组成,中心Cu(Ⅱ)的配位数为4,分别与来自L单元上的N1、N1#、O2、O2#4个原子进行配位,以金属离子为中心形成了稍微扭曲四面体结构的配位几何构型.对金黄色葡萄球菌、大肠杆菌和枯草杆菌的抑菌活性实验表明,[CuL]对3种菌均有显著的抑制作用,其抑菌活性较配体L更强.

关键词: 铜(Ⅱ)化合物 , 合成 , 结构 , 抑菌活性

一氯桥双核铜配合物:Cu2(phen)2Cl4的合成、晶体结构及性质研究

孙杰 , 林建利 , 郑岳青 , 王继扬

人工晶体学报 doi:10.3969/j.issn.1000-985X.2002.04.009

本文报导了Cu2(phen)2Cl4配合物的合成方法.X射线衍射分析表明标题配合物属单斜晶系,空间群Cc(no.9),晶胞参数:a=0.9864(2)nm,b=1.7860(4)nm,c=1.3398(3)nm,β=106.60(3)°,V=2.262(8)nm3,Dc=1.848g/cm3,F(000)=1256,Z=4.3064个独立衍射点中2812个满足F2o2σ(F2o),R1和wR2分别为0.0482和0.1066.标题配合物由双核[Cu2(phen)2Cl4]络分子组成,每个铜原子与邻菲NFED4啉配体的2个N原子和3个Cl原子配位形成畸变CuN2Cl3四方锥.配位多面体通过两氯原子形成共棱的Cu2N4Cl6双四方锥.通过氢键和芳环堆积作用,络分子形成三维网络结构.标题配合物为顺磁物质,在5～300K区间内遵循Curie-Weiss定律,χm(T+0.649)=0.405cm3*K*mol-1(χm为每摩尔Cu2+离子磁化率),其Cu2+离子的室温有效磁矩为1.8 B.M.,与Cu2+自由离子的磁矩基本相同,表明铜离子之间不存在磁交换作用.热分析显示该配合物在290℃以下非常稳定.

关键词: 晶体结构 , 双核铜配合物 , 合成 , 磁性 , 热分析

NH4GdF4的合成机理研究

姜银举 , 张小琴 , 郭海涛 , 王佐成

稀土 doi:10.3969/j.issn.1004-0277.2008.06.021

利用差热-热重分析方法,研究了Gd2O3和NH4HF2反应中间产物NH4GdF4的合成机理.结果表明,NH4GdF4是在NH4HF2熔化后与Gd2O3通过固-液相反应直接合成的;Gd2O3和NH4HF2反应的另一种中间产物为NH4F,NH4F在稍高的温度下热分解为NH3和HF;NH4F与GdF3不能合成NH4GdF4 ;GdOF也可以与NH4HF2反应合成NH4GdF4,但GdOF不是Gd2O3和NH4HF2反应的中间产物.分析了Gd2O3和NH4HF2反应不能完全合成NH4GdF4的原因.

关键词: NH4GdF4 , 合成 , 机理