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991.
通过对影响填料用氢氧化铝色度的原因进行研究,得出金属杂质含量、氢氧化铝的粒度及分布是影响填料用氢氧化铝的白度和b值的重要因素. 相似文献
992.
G. Suárez-Campos D. Cabrera-German J.A. García-Valenzuela M. Cota-Leal J.L. Fuentes-Ríos M. Martínez-Gil H. Hu M. Sotelo-Lerma 《Ceramics International》2019,45(8):10356-10363
The chemical solution deposition of Mg(OH)2 thin films on glass substrates and their transformation to MgO by annealing in air is presented. The chemical solution deposition consists of a chemical reaction employing an aqueous solution composed of magnesium sulfate, triethanolamine, ammonium hydroxide, and ammonium chloride. The as-deposited films were annealed at different temperatures ranging from 325 to 500?°C to identify the Mg(OH)2-to-MgO transition temperature, which resulted to be around 375?°C. Annealing the as-deposited Mg(OH)2 films at 500?°C results in homogeneous MgO thin films. The properties of the Mg(OH)2 and MgO thin films were analyzed by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, UV–Vis spectroscopy, and by circular transmission line model. Results by X-ray diffraction show that the as-deposited thin films have a brucite structure (Mg(OH)2), that transforms into the periclase phase (MgO) after annealing at 500?°C. For the as-deposited Mg(OH)2 thin film, a nanowall surface morphology is found; this morphology is maintained after the annealing to obtain MgO, which occurred with the evident formation of pores on the nanowall surface. The assessed chemical composition from X-ray photoelectron spectroscopy yields Mg0.36O0.64 (O/Mg ratio of 1.8) for the as-deposited Mg(OH)2 film, where the expected stoichiometric composition is Mg0.33O0.67 (O/Mg ratio of 2.0); the same assessment yields Mg0.60O0.40 (O/Mg ratio of 0.7) for the annealed thin film, which indicates the obtainment of a MgO material with oxygen vacancies, given the deviation from the stoichiometric composition of Mg0.50O0.50 (O/Mg ratio of 1.0). These results confirm the deposition of Mg(OH)2 films and the obtainment of MgO after the heat-treatment. The energy band gap of the films is found to be 4.64 and 5.10?eV for the as-deposited and the film annealed at 500?°C, respectively. The resistivity of both Mg(OH)2 and MgO thin films lies around 108?Ω·cm. 相似文献
993.
蛇纹石资源综合利用研究进展 总被引:2,自引:0,他引:2
蛇纹石作为一种重要的非金属矿物,广泛用于多种工业领域。本文介绍了蛇纹石的基本物化性质并综述了国内外近年来对蛇纹石综合利用的研究进展,提出了开发综合利用蛇纹石的绿色化学新工艺的重要意义及相关研究方向。 相似文献
994.
介绍了立式叶滤机的工作原理,分析了叶滤机在浮游物回收工段中的主要问题,并结合实际运行提出了改进措施。实践证明,采取的改进措施保证了设备的稳定运行。 相似文献
995.
中国氢氧化镁生产工艺及市场分析 总被引:1,自引:0,他引:1
介绍了我国氢氧化镁生产的主要工艺方法,并对几种工艺方法的优、缺点进行了比较,指出不同地区应结合镁资源选择适合的工艺方法;分析了国内外氢氧化镁的市场情况,氢氧化镁产大于求,市场竞争激烈。 相似文献
996.
997.
Absorption von CO2 mittels wässriger Natronlauge – Experimente und Simulationen mit dem Ansatz der Hydrodynamischen Analogien
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An approach for the simulation of separation processes in packed columns is based on hydrodynamic analogy between complex flow pattern in real equipment units and geometrically simplified model flow and is known as the Hydrodynamic Analogy (HA) approach. In this work, the HA approach was applied to reactive absorption of CO2 in aqueous sodium hydroxide solution under turbulent gas flow conditions. An extensive experimental study was carried out to measure the CO2 concentration profiles along the column height. These data provided a basis for a successful validation of the HA approach. 相似文献
998.
999.
Preparation and investigation of the combustion behavior of polypropylene/organomodified MgAl-LDH micro-nanocomposite 总被引:3,自引:0,他引:3
De-Yi Wang Andreas LeuteritzBurak Kutlu Maria Auf der LandwehrDieter Jehnichen Udo WagenknechtGert Heinrich 《Journal of Alloys and Compounds》2011,509(8):3497-3501
Layered double hydroxides (LDHs) are considered as a new emerging class of clays and they have a promising future in the field of nanocomposites due to their highly tunable properties. In this research, polypropylene/organomodified magnesium-aluminum LDH (PP/O-MgAl-LDH) composites were prepared by direct melt compounding. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to characterize the samples. Both XRD and TEM images of the composites illustrate the formation of a mixed morphology of micro and nano scale dispersion of MgAl-LDH in the matrix. Its combustion behaviors were examined via microscale combustion calorimeter (MCC), and char residues investigated by SEM. The MCC results show that the addition of Mg-Al-LDH into PP can efficiently decrease the specific heat release rate (HRR), the heat release capacity (HRC), and total heat release (THR), indicating the flame retardancy of the composite are improved. Flame retardant properties of PP/O-MgAl-LDH micro-nanocomposite were further enhanced with the increasing amounts of MgAl-LDH concentration. 相似文献
1000.
Phosphate removal from aqueous solution using a hybrid impregnated polymeric sorbent containing hydrated ferric oxide (HFO)
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