XIE Gang
,
QIU Zhuxian
,
XU Chi
,
CHEN Nainyi Northeast University of Technology
,
Shenyang
,
China. Shanghai Institute of Metallurgy
,
Academia Sinica
,
Shanghai
,
China. To whom correspondence should be addressed.
材料科学技术（英文）
Monte Carlo calculations were performed on liquid ionic solution of saturated alumina in cryolite melt containing a total of 205 ions. The local structure and radial distribution functions of the melt were computerized by Monte Carlo method at 1283 K. It has been found that there exist the complex ionic clusters such as AlOF_3~(2-), AlOF_4~(3-), AlF_4~-, AlF_5~(2-), AlOF_2~- etc., as well as oxygen-bridge and flourine-bridge ionic clusters. In the melt studied, Al~(3+) ions tend to have preferential even coordination number of 4F~- ions.
关键词:
Monte Carlo method
,
null
,
null
,
null
,
null
HOU Yan-qing
,
XIE Gang
,
TAO Dong-ping
,
LI Rong-xing
,
YU Xiao-hua
钢铁研究学报(英文版)
To confirm sub-regular solution model valid for predicting the activity of component in binary oxide systems, seven systems in the whole concentration and twelve systems presenting saturation concentration have been studied. The total average relative errors of component 1 and 2 are 3.2% and 4.1% respectively by application of the sub-regular solution model into the systems within the whole concentration. However, the total average relative errors are 16% and 1088% in the systems presenting saturation concentration. The results show that sub-regular solution model is not good for predicting the systems presenting saturation concentration, especially for the systems containing acidic or neutral oxide. The reason may be that the influence of the two types of oxide on the configuration is greater in binary oxide systems. These oxides can be present in the form of complex anion partly, Si-O, Al-O, Ti-O and so on, for example (SiO4)4-. That is contrary to sub-regular solution model which is supposed that the oxide systems consist of cation and O2-. But compared with regular solution model and quasi-regular solution model, sub-regular solution model is closer to the characteristics of actual solution and the calculated results are superior.
关键词:
sub-regular solution model
,
binary oxide system
,
activity
HOU Yanqing
,
XIE Gang
,
TAO Dongping
,
et al
钢铁研究学报(英文版)
Modified quasi-regular solution model has been got based on the sub-regular solution model and quasi-regular solution model in this article. The mixed energy parameter can be denoted a function of concentration and temperature. The three parameters of this model are fitted by the computer-assisted analysis based on the experiment data of activity at two different temperatures. Seven binary molten slag systems in the whole concentration are calculated with the application of the model and the average relative error is within 10%. That shows that the calculated result is agreement with the experiment data. Ten binary slag systems presenting saturation concentration are also calculated, but the average relative error is bigger. So the calculated result is not good agreement with the experiment data. But the calculated result is superior to regular solution model, sub-regular solution model and quasi-regular solution model.
关键词:
Activity;Binary molten slag;Modified model;Sub-regular solution
HOU Yan-qing
,
XIE Gang
,
TAO Dong-ping
,
YU Xiao-hua
,
LI Rong-xing
钢铁研究学报(英文版)
The activity of FetO is very important in ironmaking and steelmaking process. In order to predict the activity of FetO and optimize the operation conditions in ironmaking and steelmaking process, by application of regular solution model in molten slag systems, FeO-Fe2O3-SiO2 ternary system, FeO-Fe2O3-SiO2-CaO and FeO-Fe2O3-SiO2-NiO quaternary systems have been studied by the chemical equilibrium between H2/H2O gas mixture and liquid slag contained in solid iron. The values of interaction energy between cations concerning steelmaking slags have been determined by application of ferric-ferrous iron equilibrium and iron-ferric iron equilibrium. And then the activity of FetO can be calculated. The results show that the relative error is 39% in FeO-Fe2O3-SiO2 system and 18% in FeO-Fe2O3-SiO2-CaO system. The prediction of activities of FetO in the systems are in good agreement with the measurements and the regular solution model is valid for predicting the activity of FetO in complex molten slags systems. The activity of FetO in FeO-Fe2O3-NiO system have not been tested presently, and the calculated result can not be assessed.
关键词:
regular solution model
,
metallurgical molten slag
,
activity
刘建国
,
安振涛
,
张倩
,
杜仕国
,
姚凯
,
王金
材料导报
doi:10.11896/j.issn.1005-023X.2017.04.030
为评估氧化剂硝酸羟胺的热稳定性,使用标准液体铝皿于3 K/min、4 K/min、5 K/min加热速率下进行热分析.借助非等温DSC曲线的参数值,应用Kissinger法和Ozawa法求得热分解反应的表观活化能和指前因子,根据Zhang-Hu-Xie-Li公式、Hu-Yang-Liang-Xie公式、Hu-Zhao-Gao公式以及Zhao-Hu-Gao公式,计算硝酸羟胺的自加速分解温度和热爆炸临界温度,并对热分解机理函数进行了研究.设计了7条热分解反应路径,采用密度泛函理论B3LYP/6-311++G(d,p)方法对硝酸羟胺的热分解进行了动力学和热力学计算.计算结果表明,硝酸羟胺热分解的自加速分解温度TsADT=370.05 K,热爆炸临界温度Te0=388.68K,Tbp0=397.54 K,热分解最可几机理函数的微分形式为f(a) =17×(1-α)18/17.硝酸羟胺热分解各路径中,动力学优先支持路径Path 6、Path 5、Path 4和Path 1生成NO和NO2,其次是Path 2、Path 7和Path 3生成N2和N2O.温度在373 K以下时,Path 1'反应无法自发进行,硝酸羟胺无法进行自发的热分解.从热力学的角度来看,硝酸羟胺在370.05K以下储存是安全的.
关键词:
硝酸羟胺
,
热分析
,
热稳定性
,
热分解机理
,
密度泛函理论
