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单态铝酸根离子与单态硅酸根离子反应的研究 总被引:1,自引:0,他引:1
研究了碱性条件下单态铝酸根离与单态硅酸根离子的反应。实验结果表明,生成的硅铝酸盐沉淀与溶液中的Al,Si以及OH^-浓义有关。反应过程中存在过饱和现象,反应体系的OH^-浓度反应物Si/Al比影响过饱和时间和过饱和区。 相似文献
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Palmer SJ Grand LM Frost RL 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,79(1):156-160
Raman spectroscopy has been used to characterise nine hydrotalcites prepared from aluminate and magnesium solutions (magnesium chloride and seawater). The aluminate hydrotalcites are proposed to have the following formula Mg(6)Al(2)(OH)(16)(CO(3)(2-))·xH(2)O, Mg(6)Al(2)(OH)(16)(CO(3)(2-),SO(4)(2-))·xH(2)O, and Mg(6)Al(2)(OH)(16)(SO(4)(2-))·xH(2)O. The synthesis of these hydrotalcites using seawater results in the intercalation of sulfate anions into the hydrotalcite interlayer. The spectra have been used to assess the molecular assembly of the cations and anions in the hydrotalcite structures. The spectra have been conveniently subdivided into spectral features based upon the carbonate anion, the hydroxyl units and water units. This investigation has shown the ideal conditions to form hydrotalcite from aluminate solutions is at pH 14 using a magnesium chloride solution at a volumetric ratio of 1:1. Changes in synthesis conditions resulted in the formation of impurity products aragonite, thenardite, and gypsum. 相似文献
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用量子化学的电荷自洽离散变分Xα(SCC-DV-Xα)计算方法研究了CaO-Al2O3系统五种水泥矿物的结构、性能与化学键之间的关系及固溶的杂质离子Na+对矿物性能的影响。计算结果表明:Ca-O共价键强度的次序是C3A < C12A7 < CA < CA2 < CA6,且各矿物的Ca-O键强度都小于它们的Al-O键强度,与相应的水泥矿物水化活性的实验结果一致。Na+固溶于C3A结构后使其Al-O键增强,水化活化能变大,态密度减小,被认为是Na+降低C3A水化活性的主要原因。 相似文献
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An original polyamine, 2,3 di-2-aminomethyl 1,4 diaminobut-2-ene (ten), characterized by single-crystal XRD analysis, has been synthesised and leads to a new hybrid fluoroaluminate [H4ten] · (AlF5)2 by microwave heating assisted hydrothermal synthesis. The structure of [H4ten] · (AlF5)2 is ab initio determined from powder data. 相似文献
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27Al NMR and Raman spectra of alkaline aluminate solutions with 0.005 M ≤ [Al(III)]T ≤ 3 M in various M′OH solutions (M′+ = Na+, K+ and Li+) were recorded and analysed. Caustic concentrations up to 20 M were used to explore whether higher aluminium hydroxo complexes are formed at extremely high concentrations of hydroxide. A single peak was observed on the 27Al NMR spectrum of each solution. The chemical shift of this peak shifts significantly upfield with increasing [M′OH]T in solutions with [Al(III)]T < 0.8 M. This variation shows a strong dependence on the cation of the solution and practically disappears in systems with [Al(III)]T ≥ 0.8 M. For Raman spectra of solutions with [Al(III)]T = 0.8 M and [NaOH]T ≥ 10 M, the peak maximum of the symmetric ν1-AlO4 stretching of Al(OH)4− shifted progressively from ∼620 to ∼625 cm−1 and decreased in intensity with increasing [NaOH]T. In parallel, modes centred at ∼720 and ∼555 cm−1 (cf. ∼705 and ∼535 cm−1 at lower [NaOH]T, ascribed to a dimeric aluminate species appeared, and their intensities increased with increasing [NaOH]T. These variations in the 27Al NMR and Raman spectra can be interpreted in terms of contact ion-pairs formed between the cation of the medium and the well-established Al(OH)4− or the dimeric aluminate species. Assumption of higher aluminium hydroxo complex species (e.g., Al(OH)63−) is not necessary to explain the spectroscopic effects observed. 相似文献
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Zusammenfassung Es wird die Anwendung der Hochdruckflüssigchromatographie (HPLC) in Bezug auf die Identifizierung und quantitative Bestimmung von Carbonsäuren in Aluminatlaugen aus dem Bayerprozeß beschrieben. Die Vorgehensweise besteht in folgenden Teilschritten: Optimierung von HPLC Phasensystemen zur Trennung von synthetischen Gemischen von Carbonsäuren, Aufarbeitung der Aluminatlauge, semi-präparative Isolierung von Substanzen, Identifizierung auf flüssigchromatographischem Wege und durch Massenspektrometrie, quantitative Bestimmung durch Peakhöhenauswertung mit Hilfe externer Standards.
HPLC of carboxylic acids in sodium aluminate liquors from the Bayer process
Summary The paper describes the application of high performance liquid chromatography (HPLC) to the identification and quantitation of carboxylic acids in aluminate liquors from the Bayer process. The procedure comprises the following consecutive steps: optimization of HPLC phase systems employing synthetic mixtures of carboxylic acids, clean-up of the liquor, semi-preparative isolation of substances, identification by means of HPLC and mass spectrometry and estimation based on peak height measurement using external standards.
Herrn Prof. Dr. I. Halász zum 60. Geburtstag gewidment. 相似文献
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目前市售硼酸镉、钒酸钇和砷酸盐等灯用红色荧光粉,发射波长一般在610nm左右,呈桃红色。砷酸盐荧光粉掺红颜料,因而看到的是颜料的颜色,砷酸盐还有毒。因此,研制一种发射波长长,原料无毒的大红单色荧光粉有着重要的意义。关于金属离子Mn~(2+)、Cr~(3+)、Co~(2+)和Ni~(2+)在LiAl_5O_8中的发光特性已有研究。本文报导激活剂Fe~(3+)离子浓度和烧结温度对Fe~(3+)在LiAl_5O_8中发光性质的影响,并对该荧光粉的发光机制和效率等进行讨论。 相似文献