共查询到17条相似文献,搜索用时 484 毫秒
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采用光子相关光谱法测定硫酸钛白工艺中水解偏钛酸的粒度分布,研究了不同分散方法和测试条件对测定结果的影响。通过研究分散介质、分散剂及其用量,偏钛酸用量,超声分散时间及稳定时间等分散方法和测试条件,得到光子相关光谱法测定偏钛酸粒度分布的适宜分散条件。试验结果表明:采用蒸馏水为分散介质,分散剂六偏磷酸钠浓度为0.05%,50 mL分散水解偏钛酸浆料0.044 g左右,超声分散5 min后立即测定其粒度分布,此为光子相关光谱法测定水解偏钛酸粒度的最佳分散测试条件。 相似文献
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本文通过研究Mastersizer2000型激光粒度分析仪,在不同浓度的分散剂,不同的遮光度,以及不同的超声波分散时间3个方面,对测定钼粉的粒度分布测试结果所造成的影响,从而找出钼粉粒度分布测试的最佳条件,为钼粉性能的判定提供准确的数据。 相似文献
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超微粉化是实现钢渣高效利用的重要途径,粒度分布是超微粉的关键性质之一。采用激光粒度分析仪(LSA)考察了分散介质、固体质量浓度、超声分散时间以及搅拌速度对钢渣超微粉的粒度分布(用D_(10)、D_(50)和D_(90)表示,D_(10)、D_(50)和D_(90)分别是样品分布曲线中累积分布为10%、50%、90%时的等效直径)的影响。使用扫描电子显微镜(SEM)观察并计算钢渣超微粉粒度分布,将其结果与LSA测定结果对比验证。结果表明,使用激光粒度分析仪测试钢渣超微粉浓度时,无水乙醇为适宜的分散介质;固体质量浓度在0.10~0.90mg/mL范围时,随质量浓度增加,样品粒度测量结果变小,质量浓度为0.01~0.10mg/mL时,测量的D_(10)、D_(50)和D_(90)变化不大,因此适宜的测量浓度为0.01~0.10mg/mL;超声分散时间应大于30min;搅拌速度对钢渣超微粉粒度测试结果无明显影响。另外,激光粒度分析仪8次测试结果具有高度重复性,其结果与扫描电子显微镜所测粒度分布结果相一致。 相似文献
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超细WC粉末发达的表面积中贮藏着极高的表面能,对气体、液体或微粒表现出极强的吸附能力,容易自发地聚集成二次颗粒,导致样品使用常规的激光粒度分析方法不能对其进行有效的分散,激光粒度分布测试结果的峰形总是呈"拖尾"现象。本文先将试样研磨1 h,再将研磨后的试样加入无水乙醇,并在外置超声波仪中超声10 min,最后上机测试。本测试方法粒度分布曲线呈正态分布,精密度良好,激光粒度分布特征值(d(10)、d(50)、d(90))的相对标准偏差小于5%。 相似文献
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孙秀 《稀有金属与硬质合金》1991,(3):27-32
本文通过用英国MK_3圆盘离心沉降仪对43个细钨粉粒度和粒度分布定的研究,确定了离心沉降法测定细钨粉粒度及其分布的最佳测试条件。本文还对分散方法、沉降介质浓度、缓冲线起动等测试条件进行了讨论。并用光扫描比浊法、显微镜法、空气透过法和多功能图象分析仪进行了对比试验。从而确认离心沉降法是目前用来测定超细粉末粒度和粒度分布的简便而又科学的方法。 相似文献
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高纯三氧化钼激光粒度分布的测定与分析 总被引:1,自引:0,他引:1
用扫描电镜观察了高纯三氧化钼的形貌,高纯三氧化钼是长条状的单颗粒聚集成的团聚体。用激光粒度仪的干法测定了高纯三氧化钼团聚体的激光粒度分布,用水作分散剂测定了高纯三氧化钼分散体的激光粒度分布,结果表明高纯三氧化钼的激光粒度分布值与电镜测量的颗粒及颗粒团尺寸一致,这样的测试方法能全面正确地反映高纯三氧化钼粒度的特征。讨论了高纯三氧化钼激光粒度分布对后续的还原过程及钼粉质量的影响。 相似文献
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I. Kursun 《Mineral Processing and Extractive Metallurgy Review》2013,34(4):346-360
The ever-progressing development of industrial processes and products regularly requires significant progress in the development of associated measurement techniques. With the advance of technology, there have been many developments in the mining sector. Mineral particle size is a critical parameter in any process involving the liberation and separation of minerals. In most mineral processing plants, product grade and mineral recovery require sufficient mineral liberation and optimum size distribution. There are many methods of measuring mineral particle sizes. Sieving, sedimentation, microscopy, digital image processing, and laser diffraction are the most common particle size analysis methods. The shape of the particles plays an important role in the assessment of particle size distribution. Most sizing techniques, however, assume that the sample being measured is spherical, as a sphere is the only shape that can be described by a single number. Therefore different techniques can give different results for the same sample depending on this aspect. Within the scope of this study, the particle size distribution of two different sand samples (Sarikum and Senkoy) was assessed by sieving, digital image processing, and laser diffraction techniques. In addition, the convexity and circularity parameters of the samples were measured by a Morphology G device. The particle size distribution results obtained from different techniques for each sample are discussed depending on the values of convexity and circularity of the sample particles. 相似文献
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氧化铝悬浮液稳定性的研究 总被引:1,自引:0,他引:1
通过改变球磨时间、分散剂用量对氧化铝悬浮液浆料的稳定性、分散性以及流变性进行了研究。结果表明:球磨时间和分散剂用量对氧化铝悬浮液的稳定性和分散性有着显著影响。最佳球磨时间在20h左右;纯氧化铝粉体的等电点在pH=8.1左右,分散剂的加入使等电点朝低pH方向移动,且可以显著改善浆料在碱性条件下的稳定性。 相似文献
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A Bommireddi LC Li D Stephens D Robinson E Ginsburg 《Canadian Metallurgical Quarterly》1998,24(11):1089-1093
Microscopy is a useful and direct method for measuring the particle size of a suspension because, in addition to the particle size and size distribution, it provides visual detection of the shape and state of aggregation of the particles in the suspension. However, this method suffers from the shortcomings of being tedious and time consuming. In this study, a light-scattering particle size analyzer was used to determine the particle size and size distribution of a flocculated suspension. The sonication of the sample prior to and during measurement was found to be critical in ensuring that data are representative of the size distribution of the primary particles of the suspension. The light-scattering results were further confirmed by data generated using a polarized light microscope equipped with an image analyzer. 相似文献
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采用乙醇为溶剂,PVB为分散剂和粘结剂,对固相的质量分数为55%的ZrO2悬浮液的制备和性能进行了研究。通过测定悬浮液的粘度和最终沉降体积,确定最佳分散剂含量。悬浮液的制备分两个阶段:第一阶段,悬浮液由ZrO2粉、乙醇和质量分数为0.7%的PVB(分散剂)组成,球磨24h,目的是打开颗粒团聚体和润湿粉料;第二阶段,主要是使悬浮液与粘结剂的混合,分别加入不同量的PⅦ(粘结剂),球磨24h。结果表明,分散剂含量为粉体质量的0.7%时,能使ZrO2粉末得到良好的分散;当粘结剂含量少于6%时,在涂层坯体过程中容易出现裂纹;而粘结剂含量高于6%时,悬浮液中含有较多的气泡。加入0.7%分散剂和6%粘结剂,可以获得粘度适中、悬浮稳定的ZrO2悬浮液。 相似文献
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《粉末冶金学》2013,56(14):251-260
AbstractAn experimental study has been made of the effects of initial particle size on sintering kinetics in tungsten powder within the temperature range 1100–1500°C. Particle size, compacting pressure, sintering time and temperature all influence the rate of sintering. Isothermal changes in density and volume have been measured. The results indicate grain-boundary diffusion as the mechanism principally responsible for material transport in the case of particle sizes <4 μ Surface diffusion appears to bethe mechanism of material transport in compacts with particle sizes of 14– 16 μ The temperature-dependence of the rate of sintering is characterized by activation energies of 101± 2 and 72± 2 kcal/mole for fine particles (< 4 μ) and coarse particles (14–16 μ), respectively. 相似文献