Granule Structure Evolution during Powder Compaction

2002 ◽  
Vol 759 ◽  
Author(s):  
William J. Walker
Keyword(s):  
Large Fraction ◽  
Particle Size Analysis ◽  
Particle Packing ◽  
Structure Evolution ◽  
Size Analysis ◽  
Forming Process ◽  
Glass Spheres ◽  
Granule Structure ◽  
Die Compaction ◽  
Ceramics Industry

ABSTRACTDie compaction of granulated powder is a common forming process used in the ceramics industry. Glass spheres were used as a model system to investigate granule failure during die compaction. Since glass spheres are brittle, failure results in fragmentation. Particle size analysis of the resulting fragments demonstrates the statistical nature of granule failure during compaction, with some granules failing at very low applied pressures while a large fraction persist at even the highest applied loads. The results are discussed in terms of the Andreasen, Furnas and Dinger-Funk particle packing models for continuous size distributions.

scholarly journals A Mottled, Non-Lithified Paleosol in Brazil: Diagnosis by Morphological and Mineralogical Features

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 616
Author(s):  
Yuri Lopes Zinn ◽  
Camila Fernandes Miranda
Keyword(s):  
Particle Size Analysis ◽  
Size Analysis ◽  
X Ray Diffraction ◽  
Forming Process ◽  
Thin Sections ◽  
Massive Structure ◽  
Granular Microstructure ◽  
Kaolinitic Clay ◽  
Yellow Mottling

The identification of paleosols is difficult when no buried horizons or lithification occur. Here, we described the identification of a possible paleosol, its characterization, and which features supported its positive diagnosis. In a construction site, a vertical cut exposed an unusual red–yellow mottling with massive structure and channels (probably faunal), in contrast with the overlying homogeneous red Oxisol with fine granular structure. A similar but more deferrified section with white–yellow mottling also occurred nearby, and both were sampled as large clods. In thin sections, many oriented clay coatings occur along channel voids, suggesting illuviation, as well as dissolving Fe nodules and Mn coatings along planar and channel voids. X-ray diffraction showed a clay dominated by kaolinite, traces of illite, and absence of gibbsite, again contrasting with the gibsitic-kaolinitic clay of the Oxisol. We confirmed the diagnosis of a Paleoultisol due to the following incompatibilities with the overlying Oxisol: (1) massive, apedal structure, and higher bulk density; (2) clay coatings indicative of illuviation as key soil-forming process; (3) low clay contents in particle-size analysis due to cementation; (4) very low organic carbon consistent with long-term inhumation; and (5) kaolinitic–illitic clay. The unusual granular microstructure of the B horizon of the Oxisol is partly derived from disintegration and desilication of the Paleoultisol.

Mineralogical and weathering study of a red-brown earth formed on granodiorite

Soil Research ◽  
1966 ◽  
Vol 4 (2) ◽  
pp. 181 ◽  
Author(s):  
P Green
Keyword(s):  
Soil Formation ◽  
Progressive Increase ◽  
Particle Size Analysis ◽  
Parent Material ◽  
Soil Horizon ◽  
Size Analysis ◽  
Forming Process ◽  
Gains And Losses ◽  
In Situ Weathering

The development of a red-brown earth has been studied by means of mineral and fabric analyses. Data from particle-size analysis and zircon distribution indicate relative uniformity of the parent material throughout the profile, with a possible minor disconformity near the bottom of the B horizon. Calculations of gains and losses of major minerals during soil formation, based on the zircon content of each soil horizon and of the rock, show a break in the progressive increase in weathering towards the surface, suggesting that the soil is in fact a two-storied profile; micromorphological evidence supports this postulate. The constancy of the qualitative mineral assemblage, however, shows that both sola were formed entirely from the underlying weathered granodiorite. The top four horizons are interpreted as being a separate soil, probably developed from a surface movement layer composed of some material from the upper horizons of the older profile with accessions from weathering granodiorite boulders. Both soils are considered to have been formed dominantly by in situ weathering of primary minerals and removal of the weathering products by leaching; clay illuviation does not appear to have been more than a very minor soil-forming process.

Particularities of overdetermined linear systems arising in particle size analysis

1992 ◽  
Vol 2 (8) ◽  
pp. 1547-1555
Author(s):  
D. M. Calistru ◽  
R. Mondescu ◽  
I. Baltog
Keyword(s):  
Particle Size ◽  
Linear Systems ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Overdetermined Linear Systems

Acyclovir Loaded Solid Lipid Nanoparticle Based Cream: A Novel Drug Delivery System

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
EL- Assal I. A. ◽  
Retnowati .
Keyword(s):  
Drug Delivery ◽  
Drug Release ◽  
Antiviral Agent ◽  
Study Drug ◽  
Particle Size Analysis ◽  
Stability Study ◽  
Size Analysis ◽  
Solid Lipid ◽  
Dermal Delivery

Objective of the present investigation was enthused by the possibility to develop solid lipid nanoparticles (SLNs) of hydrophilic drug acyclovir. Also study vitro and vivo drug delivery. Methods: Drug loaded SLNs (ACV-SLNs) were prepared by high pressure homogenization of aqueous surfactant solutions containing the drug-loaded lipids in the melted or in the solid state with formula optimization study (Different lipid concentration, drug loaded, homogenization / stirring speed and compritol 888ATO: drug ratio). ACV - SLN incorporated in cream base. The pH was evaluated and rheological study. Drug release was evaluated and compared with simple cream- drug, ACV – SLN with compritol 888ATO and marketed cream. The potential of SLN as the carrier for dermal delivery was studied. Results: Particle size analysis of SLNs prove small, smooth, spherical shape particle ranged from 150 to 200 nm for unloaded and from 330 to 444 nm for ACV loaded particles. The EE% for optimal formula is 72% with suitable pH for skin application. Rheological behavior is shear thinning and thixotropic. Release study proved controlled drug release for SLNs especially in formula containing compritol88 ATO. Stability study emphasized an insignificant change in SLNs properties over 6 month. In-vivo study showed significantly higher accumulation of ACV in stratum corneum, dermal layer, and receptor compartment compared with blank skin. Conclusion: AVC-loaded SLNs might be beneficial in controlling drug release, stable and improving dermal delivery of antiviral agent(s).

APSAS; an Automated Particle Size Analysis System

Circular ◽  
1985 ◽  
Author(s):  
Lawrence J. Poppe ◽  
A.H. Eliason ◽  
J.J. Fredericks
Keyword(s):  
Particle Size ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Analysis System
Sign in / Sign up

Export Citation Format

Share Document