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高效液膜分离富集镍基合金镀层中稀土总量 总被引:2,自引:0,他引:2
用TBP-TTA(协同流动载体)、SPAN80和煤油高效液膜体系,研究∑RE^3+迁移行为。在适宜条件下,10min内,∑RE^3+的迁移率达99.5%以上。在同样条件下,常见共存金属离子如Fe^3+、Al^3+、Ni^2+、Cr^3+、Mo^6+、Cu^2+、Co^2+、Zn^2+、Cd^2+等均不被迁移;大量碱金属、碱土金属、Cl、NO3、ClO4、F、SiO3^2-、SO4^2-等离子也不影 相似文献
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合成了一种新的水溶性显色剂2-(2-噻唑偶氮)-5-[N,N-二羧基甲基)氮基]苯甲酸。试验了试剂与、29种金属离子的显色反应,其中11种离子能显色;同时测定了试剂的离解常数、试剂与Cu%2+,Co^2+,Ni^2+,Pd^2+,V(V)络合物的络合比、稳定常数和摩尔吸光系数等特性数据。 相似文献
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新试剂1—羟基—2—(6—溴—2—苯并噻唑偶氮)—8—氨基—3,6—萘二磺酸… 总被引:5,自引:0,他引:5
新苯并噻唑偶氮试剂-1-羟基-2-(6-溴-2-苯并噻唑偶氮)-8-氨基-3,6-萘二磺酸的合成方法简单,提纯容易,产率达73%。试剂的pKa3为6.75。是一个变色敏锐的酸碱指示剂,也可用作Cu^2+,Co^2+,Ni^2+等金属离子的显色剂。 相似文献
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非水系中钴和镧钴合金的电沉积 总被引:1,自引:0,他引:1
研究了在含Co(Ⅱ)或含Co(Ⅱ)+La(Ⅲ)的尿素-NaBr-KBr-甲酰胺体系中钴和镧钴合金的电沉积过程。测定了该体系中电极反应Co(Ⅱ)十2e=Co的传递系数及CO(Ⅱ)的扩散系数。在铜基体上得到含镧达50Wt%的镧钴合金电沉积层。 相似文献
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用稳态法求得氧化锆固体电解质内的氧位分布,从理论上阐明了钢液定氧电池参比电极的选择原则,在1600℃下,钢液含氧量小于300×10^-6时,Cr/Cr2O3参比电极优于Mo/MoO2参比电极,而钢液含氧量大于300×10^-6时,使用Mo/MoO2参比电极比Cr/Cr2O3参比电极的误差更小,氧含量极低时,不宜采用Mo/MoO2作参比电极。 相似文献
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以S-十六烷基异硫脲盐酸盐和S-苄基异硫脲盐酸 固定相,以不同浓度盐酸为展开剂,用反相纸层析法研究了两种萃取剂分别对25种金属离子的萃取能力。结果表明:在不同酸度时,S-十六烷基异硫脲盐酸盐对Sr^2+、Ba^2+等8种金属离子,S-苄基异硫脲盐酸盐对Mg^2+、Ca^2+等7种金属离子的萃取能力较强。 相似文献
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本文介绍了Co2O3-Cr2O3-Fe2O3-MnO2系高温黑颜料的合成工艺,研究分析了四种氧化物的不同配比、混合及合成温度等工艺过程对颜料呈色的影响,从而确定了含钴量较低呈色纯正的Co-Cr-Fe-Mn系高温颜料的最佳工艺条件,并利用过渡金属络合物吸收光谱理论对Co、Cr、Fe、Mn四种元素的变价离子使含Bdisplay status 相似文献
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ONACCURACYOFANALYSISOFOFHYDROGEN1前言我公司目前应用的氢气纯度分析方法有两种,一种是爆炸反应法,另一种是焦性没食子酸吸收法。几年来,人们对两种分析方法的准确性曾有过褒贬不一的评论。这里我们也谈谈自己粗浅的观点。2爆炸法测定氢气纯度一定量的氢气样品与适量的空气之均匀混合物因反应后生成液体水而引起气体体积减少,减少的体积等于参加反应气体体积之和。其中l/3为氧气,2/3为氢气。根据氢气取样量和反应前后混气体体积之差,以及氢气在反应中的体积比例关系,可计算出样品的氢气纯度。计算公式式中:A一混… 相似文献
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P. P. Budnikoff 《Journal of the American Ceramic Society》1924,7(11):817-820
The different analytical methods proposed for the evaluation of gypsum have been subjected to an experimental test. A combination method, consisting of a fusion with KHCO3 and determination of CaO by KMnO4 titration, the SO3 by Andrews method of titration of BaCrO4 has been found to give very reliable results with the least consumption of time. 相似文献
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A model is developed for the sedimentation from a suspension of two particle species of unequal densities and of different sizes. The composition and the thickness of various layers in the sediments are predicted using graphical and analytical methods. The model predictions were in excellent agreement with experimental results, when the particle size ratio was ≥ 108. When size ratio of the particles was 2.60 and 4.31 the agreement occurred in about 50 percent of the cases. 相似文献
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A novel technique serves to monitor instantaneous rates of loss of a volatile solute from a suspended drop during drying. A highly sensitive electron capture detector is used to monitor concentrations of SF6 released into a flowing gas stream from a suspended, drying drop. Simultaneously, the appearance and morphological development of the drop are monitored with a video camera. This provides the wherewithal of relating instantaneous rates of loss of the volatile solute to particular events during the development of particle morphology.
Initial experiments have been carried out with drops of aqueous solutions of glucose, sucrose, maltodextrin and coffee extract. The results clearly display the onset of the volatiles-retentive selective diffusion phenomenon. There is also substantial loss of the volatile component later in the drying process, when the drops undergo repeated ex ansion, bursting and cratering due to the formation of internaf bubbles. These experiments appear to be the first quantitative demonstration of major losses accompanying changes in drop morphology. 相似文献
Initial experiments have been carried out with drops of aqueous solutions of glucose, sucrose, maltodextrin and coffee extract. The results clearly display the onset of the volatiles-retentive selective diffusion phenomenon. There is also substantial loss of the volatile component later in the drying process, when the drops undergo repeated ex ansion, bursting and cratering due to the formation of internaf bubbles. These experiments appear to be the first quantitative demonstration of major losses accompanying changes in drop morphology. 相似文献
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ANALYSIS OF RECENT MEASUREMENTS OF THE VISCOSITY OF GLASSES 总被引:5,自引:0,他引:5
Viscosity of Simple Soda-Silicate 500° to 1400°C Comparison of the results given by English with those of Washburn, Shelton and Libman, indicates a discrepancy in the absolute values of log10 viscosity amounting to 0.6, those of Washburn et al., being relatively too high. If correction for this is made, the isothermal curves of log10 viscosity as a function of soda content are smooth up to 50% Na2O, showing no inflection. The observations as a function of temperature T are all represented within accidental error by an equation of the type where all three constants vary regularly with the composition. Change of Viscosity of Glass (6SiO2, 2Na2O) due to Molecular Substitution of CaO, MgO and Al2O3 for Na2O The effect is clearly brought out by plotting (from the results of English) the change of log10η due to the substitution as a function of temperature. The curves each show a sharp bend at a temperature between 840° and 1050°C, which is designated the aggregation temperature Ta. If we divide these curves by the corresponding percentage substituted, we get curves for each oxide which are straight and parallel below the aggregation temperatures, the slopes (increase of change of log10η per 100°C) being −0.056 (CaO), −0.055 (MgO), −0.018 (A12O3) per per cent oxide substituted. For substitution of 1/2 molecule the slopes are −0.325 (CaO), −0.23 (MgO) and −0.18 (Al2O3) per 100°. At the aggregation temperature the change of log10η per per cent is a minimum, 0.03 to 0.06 for CaO, 0.12 for MgO, 0.07 for Al2O3. Evidence of Aggregation in Glasses, from viscosity Measurements The sharp bends in the plots of change of log10η due to substitution of an oxide for Na2O, suggest the beginning of molecular aggregation at these temperatures. These aggregation temperatures are close to the devitrification temperatures, but the effect on the viscosity curves cannot be due to actual devitrification since it does not change with time. Taking the aggregation temperatures as equal to devitrification temperatures, additional isotherms are roughly sketched into the equilibrium triangle of the system Na2O-CaO-SiO2. Change of Viscosity of Glass (4SiO2, 2Na2O) due to of Substitution of B2O3 for SiO2 The change of log10η (from the results of English) is plotted as a function of temperature, and also the change of log10η per per cent B2O3. The curves are more complex than for the substitution for Na2O. 相似文献
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面对日益激烈的市场竞争,摩托车油箱外观质量越来越成为影响销售的因素之一。文章介绍了改进工艺后的油箱涂装,该涂装体系提高了油箱外观的丰满度,降低了油箱涂装的生产成本。 相似文献
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用两个形状指数表征粉煤灰颗粒形貌的研究 总被引:5,自引:0,他引:5
引用两个形状指数表征颗粒形状的概念,即先将颗粒形状近似为椭圆,再将椭圆图像分离:以圆为基准的颗粒宏观形状指数δ;以光滑椭圆为基准的颗粒轮廓凹凸度,即微观形状指数ζ。分析和发展了近似椭圆模型。并运用图像分析仪对粉煤灰、水泥样品进行实验。结果表明,粉煤灰颗粒的两个形状指数δ和ζ都大于水泥颗粒。证明粉煤灰颗粒的球形度、表面光滑度优于水泥,而且,随着粒径增大,δ和ζ呈下降趋势,表明磨制颗粒越粗。(?)粒形状越不规则。文中还运用近似椭圆模型再现了颗粒的模拟图像。 相似文献