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Both whisker and nanometer MgSO4·5Mg(OH)2·3H2O(MOS) were prepared by hydrothermal method at 140℃ for different times, using NaOH and MgSO4·7H2O as raw materials. The MgSO4·5Mg(OH)2·3H2O part- icles were characterized by powder X-ray diffraction(XRD),thermal analysis(TGA-DSC), infrared spectroscopy(FT-IR),transmission electron microscopy(SEM) and scanning electron microscopy(TEM). The size distribution in whisker-like and nanocrystalline materials are in the range of 10~50μm and 10~20nm respectively. The whisker MOS is metastable phase in MgSO4-NaOH-H2O system at 140℃,whereas nanometer MOS is stable phase. 相似文献
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水合铵硼氧酸盐及其饱和溶液的FTIR和Raman光谱研究 总被引:1,自引:0,他引:1
研究了NH4B5O8·4H2O和(NH4)2B8O13·6H2O及其饱和溶液于20℃的FTIR和Raman光谱,对振动频率进行了归属.根据振动光谱特征,预测(NH4)2B8O13·6H2O中所含基本结构单元为[B7O 11(OH)·B(OH)3]2-.首次将Raman光谱中516cm-1处的强散射峰归属为这一多聚硼氧配阴离子的对称脉冲振动峰,并对以上2种铵硼氧酸盐饱和溶液中硼氧配阴离子的存在形式{B(OH)3,[B3O3(OH)4]-和[B5O6(OH)4]-}和相互作用机理进行了探讨. 相似文献
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Pitzer混合参数对HCl-NaCl-H2O体系溶解度预测的影响 总被引:1,自引:0,他引:1
This paper reports the results of solubility calculation of the phase system HCl NaCl H2O at 25 ℃ when θHNa (interactions of two species with the same charge) and ΨHNaCl (interactions of three species) were changed by +10% and -10%. The results indicated that the effects of the two kinds of interactions on the calculated solubility of the system were regular. The calculated solubilities of the system did not vary while the two interactions were increased and decreased simultaneously. The solubility data of the system changed greatly as one interaction was increased and the other decreased. This study is significant for the chemical technology of salting out salts from the water salt system. 相似文献
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文献中未见MCl-HCl-H2O(M=Li、Na、K、Rb、Cs)三元体系25℃时在HCl全浓度范围内溶解度预测的报道。本文报道应用Pitzer的离子相互作用模型,系统地对0.1~16.0 mol·kg-1浓度范围内HCl的活度系数和渗透系数值进行最小二乘法拟合,得到一套优于文献上报道的作用参数。用这一套参数和本文报道中五个三元体系得到的θmn和φmnx,对溶解度预测获得满意结果。本方法可以推广到其它任何温度时、甚至相关四元和五元体系的溶解度预测,可以减少繁琐的实验测定,并对于利用HCl从盐卤中盐析分离LiCl、RbCl和CsCl的相化学工艺计算具有实际意义。 相似文献
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Y3Al5O12∶Eu3+磷光体的溶胶-凝胶法合成及发光特性 总被引:3,自引:0,他引:3
以金属烷氧基化合物为原料,采用溶胶-凝胶法在1 000℃下合成了Eu3+掺杂的Y3Al5O12(YAG)磷光体.利用TG-DSC,XRD和发光光谱等对样品进行了表征.结果表明,YAG∶Eu3+的晶相形成温度为991℃.Eu3+在非晶态和晶态YAG中的发射光谱有明显差异.研究了Eu3+含量和烧结温度对Eu3+的5D0→7F1和5D0→7F2发射峰强度的影响.随煅烧温度的升高和Eu3+浓度的增加,Eu3+发射峰强度增强. 相似文献
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三元系RbCl-C2H5OH-H2O液固相平衡及其物化性质研究 总被引:2,自引:0,他引:2
The isothermal solubility and physico-chemical properties (density, refractive index) of ternary system RbCl-EtOH-H2O at 25℃ and 50℃ have been firstly investigated by means of self-made micro-equilibrium and sampling apparatus .The compositions of liquid and solid at equilibrium state were determined, and the problem of analysis of ethanol content in system was properly solved. The phase diagram was drawn by the TPD phase-diagram computer program developed by us. Three empirical formulae were proposed to correlate the solubility, density and refractive index respectively. No demixing phenomena was observed in the range of temperature related in this study. 相似文献
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某些有机溶剂加入无机水盐体系能较大地改变无机盐在水溶液中的溶解度 ,反之 ,某些盐类也可显著地影响双液系组分之间的相对挥发度 ,这方面的理论研究和应用研究已有较多报道[1 ,2 ] 。利用一些有机溶剂的强盐析作用 ,以期实现对某些混合盐类的分离和纯化 ,在盐卤工业等领域具有很重要的意义。Nikolskaya等[3] 和潘焕泉等[4] 分别测定了三元系Li2 SO4 C2 H5OH H2 O在不同温度 (- 2 0~ 5 0℃ )下的互溶度 ,没有发现该体系产生分层现象 ,确定了各温度下的平衡固相皆为Li2 SO4·H2 O。Aravamu dan[5] 及… 相似文献