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Beer's law experiment, variable-temperature spectral experiment of UV-Vis absorption, 1H NMR, and measurement of magnetic moment were conducted for NiTMPyP in aqueous solution. It was found that Beer's law was obeyed in concentration range 8× 10-7-2×10-5.mol•dm-3.With the temperature increasing from 0 ℃ to 95 ℃, the isosbestic point appeared at 435 nm and the lowest downfield 1H NMR peak narrowed gradually and shifted to upfield. The magnetic moment is 2.07 BM in D2O at 30 ℃, but in the D2O-CD3COCD3 mixed solvent there was no evidence for the existance of paramagnetic species. These results show that NiTMPyP exists in aqueous solution as an equilibrium mixture of diamagnetic, four-coordinate nickel (Ⅱ) and paramagnetic, sir-coordinate nickel (Ⅱ) complexed by water molecules in the axial position. The thermodynamic parameters of the axial-coordinated reaction were △S?=-178.6 J•K-1•mol-1, △G298K?=-1.6 kJ•mol-1. 相似文献
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讨论了一类鞍点型线性半连续动力系统,给出了阶1周期解存在性、唯一性、稳定性以及阶2周期解不存在性的条件,并指出在一定的条件下,系统可以存在无穷多个阶1周期解.最后给出了相应理论结果的数值模拟. 相似文献
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水热条件对立方状Co3O4形貌的影响 总被引:4,自引:0,他引:4
研究了原料浓度、溶液酸度、水热反应温度和时间以及陈化方式等条件对立方状Co3O4形貌和粒度的影响,采用XRD,TEM和IR等手段跟踪反应过程,并表征产物,对水热过程中的相转变和尖晶石相Co3O4的水热形成机理进行了初步探讨 相似文献
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γ-Mn2O3with one dimensional (1D) nanostructure was prepared via hydrothermal treatment followed by decomposition. Transmission electron microscope (TEM) images showed that nanorods coexisted with nanotubes, with the aspet ration higher than 20 and the inner diameter of nanotubes about 10 nm. TGA-DTG, XRD and TEM were used to characterize the products. The factors of hydrothermal treating temperature, holding time and high concentration of SDS played important roles in the formation and growth of the 1D nanostructures. 相似文献