Experimental XRF Calculation Method with Correction for a Polydisperse Material Particle Size

1991 ◽  
Vol 35 (B) ◽  
pp. 1055-1061
Author(s):  
V. V. Zagorodny ◽  
V. I. Karmanov
Keyword(s):  
Particle Size ◽  
Sample Preparation ◽  
Particle Size Distribution ◽  
Fluorescence Intensity ◽  
Calculation Method ◽  
Multicomponent Mixtures ◽  
Material Particle ◽  
Polydisperse Material ◽  
Multicomponent Material ◽  
Welding Materials

AbstractA new experimental calculation method for polydisperse (i.e. heterogeneous) multicomponent material analysis has been developed using the dependence of element fluorescence intensity on the particle size and its distribution in the specimen. It is shown that correction of the influence of matrix particle size is possible using this experimental calculation method. For its application, the information on particle size distribution for each of the components is sufficient. Sample preparation includes only the pelleting of specimens under standard conditions. The efficiency of the method proposed is demonstrated by the analysis of the multicomponent mixtures of welding materials.

Assessment of Lost Circulation Material Particle-Size Distribution on Fracture Sealing: A Numerical Study

2022 ◽  
pp. 1-15
Author(s):  
Lu Lee ◽  
Arash Dahi Taleghani
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Numerical Study ◽  
Fluid Loss ◽  
Material Particle ◽  
Lost Circulation ◽  
Fracture Sealing ◽  
Discrete Element Methods ◽  
Lost Circulation Materials

Summary Lost circulation materials (LCMs) are essential to combat fluid loss while drilling and may put the whole operation at risk if a proper LCM design is not used. The focus of this research is understanding the function of LCMs in sealing fractures to reduce fluid loss. One important consideration in the success of fracture sealing is the particle-size distribution (PSD) of LCMs. Various studies have suggested different guidelines for obtaining the best size distribution of LCMs for effective fracture sealing based on limited laboratory experiments or field observations. Hence, there is a need for sophisticated numerical methods to improve the LCM design by providing some predictive capabilities. In this study, computational fluid dynamics (CFD) and discrete element methods (DEM) numerical simulations are coupled to investigate the influence of PSD of granular LCMs on fracture sealing. Dimensionless variables were introduced to compare cases with different PSDs. We validated the CFD-DEM model in reproducing specific laboratory observations of fracture-sealing experiments within the model boundary parameters. Our simulations suggested that a bimodally distributed blend would be the most effective design in comparison to other PSDs tested here.

Electron Microscopy and Chemistry

1967 ◽  
Vol 25 ◽  
pp. 6-7
Author(s):  
John Turkevich
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Electron Microscope ◽  
Sample Preparation ◽  
Particle Size Distribution ◽  
Colloidal Particles ◽  
Catalyst Characterization ◽  
Practical Application ◽  
Reinforcement Fiber ◽  
Polymer Research

During the last twenty-five years there has been a marked increase in the number of chemical problems that have been attacked by the various methods of electron microscopy. In addition there has been a development of sophistication in the diverse techniques of sample preparation. The electron microscope has been used in fundamental studies to characterize the texture of matter—that state of organization of matter more complex than that of larger molecules and smaller than the details that can be revealed by optical microscopy. This has brought about an understanding of the size and shape of colloidal particles, the pore distribution of membranes, the topology of surfaces and the density and character of dislocations in solids. Particle size distribution curves obtained with the electron microscope have found widespread practical application in the pigment manufacture, rubber reinforcement, fiber studies, catalyst characterization, and polymer research.

Combustion Synthesis of β-SiAlON Using 3D Ball Milling

2017 ◽  
Vol 898 ◽  
pp. 1717-1723 ◽  
Author(s):  
Xue Mei Yi ◽  
Shota Suzuki ◽  
Xiong Zhang Liu ◽  
Ran Guo ◽  
Tomohiro Akiyama
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Combustion Synthesis ◽  
Ball Mill ◽  
Raw Materials ◽  
Raw Material ◽  
Size Distributions ◽  
Particle Size Distributions ◽  
Material Particle

Combustion synthesis (CS) of β-SiAlON was conducted using a 3D ball mill, with a focus on the effect of the 2D/3D ball mill premixing conditions on the CS raw material particle size as well as on the yield and grain shape of the final products. The results showed that the particle size distribution of the raw materials was significantly affected by the premixing conditions. Various particle sizes and particle size distributions could easily be obtained by using a 3D mill instead of a 2D mill due to the complex biaxial rotation movement of 3D milling. The particle size was more sensitive to the rotation ratio (vertical spin/horizontal spin, Vv/Vh) than the rotation rate when using 3D milling. Finally, β-SiAlON with less than 5 mass% unreacted Si was obtained using premix milling conditions of 135×200 [vertical spin (rpm) × horizontal spin (rpm)]. The grain shapes of the final products were clearly influenced by the particle size distribution of the raw mixtures.

Effects of raw material particle size distribution on the characteristics of Scots pine sawdust fuel pellets

2008 ◽  
Vol 89 (12) ◽  
pp. 1324-1329 ◽  
Author(s):  
Dan Bergström ◽  
Samuel Israelsson ◽  
Marcus Öhman ◽  
Sten-Axel Dahlqvist ◽  
Rolf Gref ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Scots Pine ◽  
Raw Material ◽  
Material Particle ◽  
Pine Sawdust ◽  
Fuel Pellets

The implications of sample preparation on the particle size distribution of soil

2019 ◽  
Vol 182 (2) ◽  
pp. 277-285 ◽  
Author(s):  
Neda Vdović ◽  
Kristina Pikelj ◽  
Irena Jurina ◽  
Maja Ivanić ◽  
Nadia Dunato ◽  
...  
Keyword(s):  
Particle Size ◽  
Sample Preparation ◽  
Particle Size Distribution ◽  
Size Distribution

scholarly journals Fluorescence Lifetime and Intensity of Thioflavin T as Reporters of Different Fibrillation Stages: Insights Obtained from Fluorescence Up-Conversion and Particle Size Distribution Measurements

2020 ◽  
Vol 21 (17) ◽  
pp. 6169
Author(s):  
Nataliya R. Rovnyagina ◽  
Gleb S. Budylin ◽  
Yuri G. Vainer ◽  
Tatiana N. Tikhonova ◽  
Sergey L. Vasin ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Fluorescence Intensity ◽  
Globular Proteins ◽  
Thioflavin T ◽  
Physical Parameters ◽  
Average Particle ◽  
Fluorescence Measurements ◽  
Tht Fluorescence

Thioflavin T (ThT) assay is extensively used for studying fibrillation kinetics in vitro. However, the differences in the time course of ThT fluorescence intensity and lifetime and other physical parameters of the system, such as particle size distribution, raise questions about the correct interpretation of the aggregation kinetics. In this work, we focused on the investigation of the mechanisms, which underlay the difference in sensitivity of ThT fluorescence intensity and lifetime to the formation of protein aggregates during fibrillation by the example of insulin and during binding to globular proteins. The assessment of aggregate sizes and heterogeneity was performed using dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA). Using the sub-nanosecond resolution measurements, it was shown that the ThT lifetime is sensitive to the appearance of as much as a few percent of ThT bound to the high-affinity sites that occur simultaneously with an abrupt increase of the average particle size, particles concentration, and size heterogeneity. The discrepancy between ThT fluorescence intensity and a lifetime can be explained as the consequence of a ThT molecule fraction with ultrafast decay and weak fluorescence. These ThT molecules can only be detected using time-resolved fluorescence measurements in the sub-picosecond time domain. The presence of a bound ThT subpopulation with similar photophysical properties was also demonstrated for globular proteins that were attributed to non-specifically bound ThT molecules with a non-rigid microenvironment.

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