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131.
Kinetics of the Complex of Terbium o-methylbenzoate with 1,10-Phenanthroline. Synthesis,decomposition mechanism 总被引:1,自引:0,他引:1
The complex of [Tb2(o-MBA)6(PHEN)2] (o-MBA: o-methylbenzoate and PHEN:1,10-phenanthroline) were synthesized and characterized by elemental analysis and IR spectroscopy.
The thermal behavior of [Tb2(o-MBA)6(PHEN)2] in dynamic nitrogen atmosphere was investigated by TG-DTG techniques. The thermal decomposition process of the [Tb2(o-MBA)6(PHEN)2] occurred in three consecutive stages at Tp 294, 427 and 512°C. The kinetic parameters and mechanisms of first decomposition stage from analysis of the TG-DTG curves
were obtained by the Malek method.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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一种研究聚合物非等温结晶动力学的方法 总被引:19,自引:2,他引:17
作者基于多年对聚合物结晶动力学方面研究的工作积累,联合Avrami方程和Ozawa方程,提出了一种研究聚合物非等温结晶动力学的新方法.该方法既克服了使用Ozawa方程所获得的数据点过少,常常出现非线性,不能获得可靠的动力学参数的缺点,又克服了使用经Jeziorny修正的Avrami方程所获得的表观Avrami指数无法准确预测非等温过程成核生长机理的缺点.该方法已成功用于多种聚合物体系,被国内外学者引用数百次,已成为研究聚合物非等温结晶动力学一种有效方法. 相似文献
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136.
The model of weight loss taking place in each step of a scheme of consecutive reactions was applied to nonisothermal thermogravimetric records of bromomethylated poly(2,6-dimethyl-1,4-phenylene oxide). The release of HBr was found to be faster in air than in nitrogen. A significant reduction in the apparent activation energy of dehydrobromination as compared with decomposition of the nonbrominated polymer was ascribed not only to a reduction in the activation energy of the initiation reaction, but also to an increase in the order of the termination reaction (from 1 for the nonbrominated polymer to 2 for the highly brominated polymer). 相似文献
137.
Using thermogravimetric analyses as well as isothermal gravimetric measurements, the thermal stability of the iron(III) nitrate nanohydrate has been determined. Several decomposition stages are the result of melting, evaporation and hydrolysis processes occurring in the salt—water system in the temperature range of 20–400°C. Some of the intermediates and the final product (-Fe2O3) are characterized by means of chemical analyses, X-ray diffraction patterns and IR spectra.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
138.
High Accuracy Numerical Simulation of Non-Isothermal Viscoelastic Polymer Fluid Past a Cylinder北大核心CSCD
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采用同位网格有限体积(coupled and linked equations algorithm revised,CLEAR)方法求解黏性和XPP (eXtended Pom-Pom)黏弹性流动的控制方程,基于延时修正方法构造了动量和本构方程对流项的高精度AVLsmart格式。首先,为了验证该文方法的有效性,对不同Reynolds数下不可压黏性流体圆柱绕流问题进行了模拟。随后,对等温及非等温不可压XPP黏弹性流体圆柱绕流问题进行了有效模拟,给出了速度矢量、应力分量、拉升量以及温度的分布规律,分析了We数对水平速度、法向应力及拉升量的影响。该文研究成果能为精确预测复杂型腔纤维增强黏弹性聚合物熔体动态充填过程提供理论基础。 相似文献
139.
Ek. Todorova 《Journal of Thermal Analysis and Calorimetry》1996,46(1):187-192
To improve the separation of the dihydrate and hemihydrate phases, different sample masses, heating rates and crucibles were used. A TG-DTA method was developed for the determination of water evolved from CaSO4·xH2O. The new crucible introduced for the Q-1500D MOM derivatograph gives a possibility for the evolved water to be determined independently from the TG and DTA curves.I am very grateful to Prof. Pelovski for the opportunity to use the Gypsum & Lime collection. This study was supported by the National Fund Science Research-Bulgaria. 相似文献
140.
M. R. P. Kurup E. Lukose K. Muraleedharan 《Journal of Thermal Analysis and Calorimetry》2000,59(3):815-825
Iron(III) complexes of o-vanillin oxime have been synthesized and characterized by different physicochemical techniques. The complexes containing
thiocyanate, iodide and sulphate ionshave been subjected to non-isothermal decomposition studies in N2 using TGand DTG techniques. The kinetic parameters for both stages of decomposition of these complexes were evaluated by
weighted least-squares method using the general approach as well as the Coats–Redfern and Horowitz–Metzger equations. The
results indicate that the values of kinetic parameters obtained by these three different approaches agree well.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献