Particle Size Distributions, Hygroscopicities, Surface Factors, Colloid Contents, and Total Surface Areas of Ceramic Raw Materials and the Relations among Them

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.

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Electrospray Ionization of Polymers: Evaporation, Drop Fission, and Deposited Particle Morphology1

Journal of Micro and Nano-Manufacturing ◽

10.1115/1.4028505 ◽

2015 ◽

Vol 3 (1) ◽

Cited By ~ 5

Author(s):

Marriner H. Merrill ◽

William R. Pogue ◽

Jared N. Baucom

Keyword(s):

Particle Size ◽

Electrospray Ionization ◽

Solute Concentration ◽

Experimental Results ◽

Size Distributions ◽

Particle Size Distributions ◽

Concentration Gradients ◽

Surface Areas ◽

Fundamental Challenge ◽

Coulomb Fission

The fundamental challenge of nanomanufacturing is to create, control, and place immense quantities of nanoscale objects controllably over large surface areas. Electrospray ionization (ESI) has the potential to address this challenge due to its simplicity, applicability to a broad range of materials, and intrinsic scalability. However, the interactions between electrospray parameters and final deposited morphology are not well understood. Experimental results are combined with physics-based models to explain how observed particle size distributions are caused in the spray by evaporation and Coulomb fission of drops with solute concentration gradients.

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Uncertainty in the Surface Area of Crushed Glass in Rate Calculations

MRS Proceedings ◽

10.1557/opl.2015.331 ◽

2015 ◽

Vol 1744 ◽

pp. 145-152

Author(s):

William L. Ebert ◽

Charles L. Crawford ◽

Carol M. Jantzen

Keyword(s):

Particle Size ◽

Surface Area ◽

Size Fraction ◽

Mesh Size ◽

Glass Mass ◽

Size Distributions ◽

Particle Size Distributions ◽

Test Response ◽

Surface Areas ◽

Opposing Effects

ABSTRACTSeries of 7-day Product Consistency Tests (PCTs) were conducted with ARM-1 glass using the -100+200 mesh size fraction and several sub-fractions to measure the sensitivity of the test response to the distribution of particle sizes. Separate samples were prepared for testing by dry sieving and wet sieving, and the particle size distributions and PCT responses were measured for each fraction. Triplicate tests were conducted at 90 °C using a water/glass mass ratio of 10.0 with each size fraction. Test results are evaluated regarding the sensitivity of the test response to the particle size distributions and, conversely, the uncertainty due to calculating the surface areas (and dissolution rates) by modeling the particles as spheres. These analyses show the solution feedback effects of dissolved glass constituents (i.e., the reaction affinity) counteract the effects of the glass surface areas provided by different particle size distributions on the test response. The opposing effects of the surface area on the amount of glass dissolved and on the glass dissolution rate moderate the sensitivity of the PCT response to the particle size distribution.

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