共查询到19条相似文献,搜索用时 156 毫秒
1.
激光粒度分析仪测定氢氧化铝细颗粒方法的探讨 总被引:1,自引:0,他引:1
针对马尔文2000型激光粒度分析仪在氢氧化铝分析中对25μm粒径以下细颗粒的分析不太敏感,难以满足氧化铝生产分解过程对粒度控制的要求,对试验样品采用一些非常规的特殊处理方法,以提高细小颗粒在处理过样品中所占的体积百分比;研究了不同的样品处理方式对分析结果的影响。试验结果表明,只有对洗涤、过滤后的湿样进行分析,才能对分解料浆样品中的细颗粒的粒度分布进行准确地分析,得到满足试验和生产过程控制精度的结果。 相似文献
2.
采用小角X射线散射法,在普通的X射线衍射仪上实现纳米级氧化锆粒度分布的表征;并按照国标(GB/T13221-2004)的标准,使用SAXS程序计算出纳米氧化锆的粒度分布范围在1-36nm之间。与纳米氧化锆的TEM图像相比较,对比结果表明该方法测得的纳米氧化锆粒度可靠。 相似文献
3.
测试了高氯酸·[四氨·双(5-硝基四唑)]合钴(Ⅲ)原样及其超细样品的粒度分布。结果表明,超细样品和原样均呈双峰/多峰分布,且其粒度分布具有分维特征。原样的分维数较低为1.80,3个细化样的分维数均较高,为2.32~2.42。分析认为,研磨时间从0延长至60min,对应样品粒度分布分维数增大,符合通常的粒度分布规律。研磨时间从60min延长至150min期间,对应样品中亚微米和纳米粒子含量较高,团聚较严重,使粒度分布发生异常,粒度分布分维数计算中的相关系数有所减小,分维数计算值不再增加。分维数可在一定程度上反映超细粒子团聚行为的严重程度。 相似文献
4.
5.
6.
活性炭吸附性能与其粒度分布分形维数的关系研究 总被引:1,自引:1,他引:0
采用数字显微系统和图像处理技术算得5种活性炭样品的粒度分布分形维数值,探讨了活性炭的吸附性能与其粒度分布分形维间的关系.结果表明,活性炭样品的平衡吸附量与粒度分布分形维数值均随细颗粒活性炭含量的增加而逐渐增大.进一步的研究表明,活性炭样品的平衡吸附量与其粒度分布分形维数值存在正相关关系. 相似文献
7.
镍纳米粉的阳极弧等离子体制备与粒度研究 总被引:1,自引:0,他引:1
采用阳极弧放电等离子体方法成功制备了高纯镍纳米粉体并对其粒度进行表征.采用X射线衍射(XRD)测试样品的物相和结构,并用Scherrer公式计算晶粒粒度;采用透射电子显微镜(TEM)分析样品的形貌、结构和粒度分布;采用表面吸附仪测定样品的N2吸附-脱附等温线,并由BET理论模型计算出样品的比表面积和颗粒粒度.实验结果表明:本法所制备的镍纳米的晶体结构与相应的块体材料基本相同,为fcc结构的晶态,呈规则的球形链状分布,比表面积为14.23m2/g,粒径范围分布在(20~70) nm,平均粒径为47 nm,三种方法测得的结果基本一致. 相似文献
8.
9.
随着各种原理粒度仪的广泛使用,仪器用的标准样品从品种到数量均有了更高的需求.通过对德国(SiC-P6000)和GBW12000标准样品进行微观形貌分析和粒度分布测试,SiC-P60000粒度分布范围窄,不能覆盖量程的测试范围,GBW12000为球形颗粒,大小均匀,适合校验某点的准确性.而标准样品价格昂贵,本文提出用廉价易得的氢氧化铝代替标准样品,为粒度仪标准样品的研制及粒度仪标准测试方法建立提供参考. 相似文献
10.
11.
James Clarke John F. Gamble John W. Jones Mike Tobyn Richard Greenwood Andy Ingram 《Advanced Powder Technology》2019,30(5):920-929
For image based particle characterisation approaches one of the most common discussion points is determining the number of particles required to have statistical confidence that the measurement is able to adequately describe the distribution of the sample. This topic becomes significantly more challenging when applied to the extraction of single component size distributions from multi-component samples.The aim of this work was to propose a means to accurately assess the particle number requirements using a method specific approach. The method applies a sub-sampling method to the original imaged dataset in order to provide an understanding of the impact of sub-sampling on the ability to accurately reproduce the original distribution.The method was applied to understand the particle number requirements for two batches of theophylline anhydrous with varied particle size distributions, using the input size distribution to guide the requirements for the subsequent multi-component samples of both materials.The results demonstrate the utility of the method to determine the appropriate number of particles required to recreate the size distributions. Whilst the minimum number of particles required to be sampled can be estimated, how those particles are sampled can also affect the validity of the measurement and must be taken into consideration. 相似文献
12.
《Drug development and industrial pharmacy》2013,39(8):895-900
In this study, a rapid and accurate particle size determination method using a light-scattering particle size analyzer was developed to measure the particle size and size distribution of a suspension containing three solid components: clotrimazole, triamcinolone, and sarafloxacin, which have different refractive indices. To ensure that data represent the size distribution of the primary particles of the suspension, the optimal sonication prior to and during measurement was detemined. It was found that the results obtained using the average relative refractive index (RRI) of the three components agreed with the results obtained using three individual RRIs. In addition, the results from two analysts demonstrated good reproducibility of this method. The size distribution data of the suspension were also compared to those of the bulk drugs. The results showed that the median particle size of this three-component suspension is relatively close to that of clotrimazole, which accounts for 80% of solid particles in the suspension. Furthermore, the results obtained using the light-scattering technique were comparable to those obtained using a polarized light microscope equipped with an image analyzer, indicating acceptable accuracy of this technique. 相似文献
13.
14.
15.
粉体粒度及粒度分布是粉体颗粒最重要的特性。以稀土永磁材料NdFeN为例,采用激光散射法(干法和湿法)和扫描电镜法对其粒度进行了分析,并比较了三种方法的测试结果。测试结果显示,粒度分析时样品的充分分散是准确测量的基础。将显微镜的直观与激光粒度仪的快速、准确和方便结合起来,对于保证粒度分析结果的可靠性非常有用。 相似文献
16.
Krejcová K Rabisková M Vetchý D Polásek E Tomásek V Prokopová A 《Drug development and industrial pharmacy》2006,32(5):585-593
Pellets containing drugs of different properties were prepared in a Rotoprocessor in order to study changes in the formulation process and resulting pellet characteristics. Diltiazem hydrochloride, diclofenac sodium, and theophylline were chosen as model drugs. Pellet size distribution, sphericity, density, hardness, friability, and repose angle were determined using standard methods. The amount of water as a wetting agent necessary for successful pellet formulation was observed for each sample and changed depending on drug solubility, concentration, and particle size. The pelletization of freely soluble diltiazem hydrochloride required 24.8-23.1% of the wetting agent and its amount decreased as the drug concentration increased. The demand for water in the formulation of theophylline pellets was 31.0-34.4% and it increased with increasing drug concentration. The pellet samples containing both drugs were easy to prepare. However, the cohesion of micronized diclofenac sodium particles negatively influenced both the pellet size distribution and the formulation process itself. When the drug concentration exceeded 40%, it was not possible to produce pellets of an appropriate size and the process was not reproducible. 相似文献
17.
颗粒统计平均粒径及其分布的表征 总被引:14,自引:0,他引:14
讨论了颗粒形状和大小的表示、粒径测定、平均粒径和粒径分布的表征等问题,用实例比较了3种粒径分布较典型的乳液样品的各种平均粒径差异;根据粒子数计算公式的含义分析和统计平均粒径的物理意义,认为用于计算粒子数的平均粒径应为体均粒径,提出有关的一些建议。 相似文献
18.
激光粒度分析结果在形貌分析中的应用 总被引:3,自引:0,他引:3
激光粒度分析仪通常只用于颗粒大小与分布的测定。通过比较粉体颗粒的激光粒度分析与扫描电镜分析的结果,发现,激光粒度分析仪所测定的粒度分布函数同时包含了一些形貌分析信息。利用这些信息可为试样进一步作SEM测定创造了条件。 相似文献
19.
《Advanced Powder Technology》2021,32(11):4110-4119
The aim of this work was to examine the impact of equilibrium judgment criteria on adsorption test of samples with different adsorption kinetics and determine how long it takes for different particle size samples to attain equilibrium adsorption data. The adsorption data of coal samples with three different particle sizes was obtained by manometric method at the different time intervals. High pressure CH4 adsorption equilibrium measurements and low pressure N2 and CO2 adsorption measurements were carried out for coal samples of eight various particle sizes. The results demonstrated that both the equilibrium and disequilibrium adsorption data satisfied the Langmuir equation. The Langmuir volume (VL) increased on the equilibrium time increase and it became more remarkable with increasing particle size. The Langmuir pressure (PL) showed an opposite and more obvious trend. When the particle size of the coal sample decreased from 2 to 4 to <0.074 mm, the adsorption equilibrium time (AET) required for the adsorption isotherm testing declined rapidly from 389 to 5 h. This research is of some enlightening significance for comparing the adsorption characteristics of samples with different adsorption kinetics (adsorbent, temperature, particle size, etc.). 相似文献