Particle size distributions, PM2.5 concentrations and water-soluble inorganic ions in different public indoor environments: a case study in Jinan, China

2012 ◽  
Vol 7 (1) ◽  
pp. 55-65 ◽  
Author(s):  
Can Dong ◽  
Lingxiao Yang ◽  
Chao Yan ◽  
Qi Yuan ◽  
Yangchun Yu ◽  
...  
Keyword(s):  
Particle Size ◽  
Inorganic Ions ◽  
Water Soluble ◽  
Indoor Environments ◽  
Size Distributions ◽  
Particle Size Distributions ◽  
Water Soluble Inorganic Ions

scholarly journals Particle size distributions by transmission electron microscopy: an interlaboratory comparison case study

Metrologia ◽  
2013 ◽  
Vol 50 (6) ◽  
pp. 663-678 ◽  
Author(s):  
Stephen B Rice ◽  
Christopher Chan ◽  
Scott C Brown ◽  
Peter Eschbach ◽  
Li Han ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Particle Size ◽  
Interlaboratory Comparison ◽  
Size Distributions ◽  
Particle Size Distributions ◽  
Transmission Electron

Miniemulsion Polymerization Stabilized by a Well-Defined, Amphiphilic Gradient Poly(styrene-co-acrylic acid) Copolymer

2006 ◽  
Vol 59 (8) ◽  
pp. 544 ◽  
Author(s):  
Catherine Lefay ◽  
Maud Save ◽  
Bernadette Charleux ◽  
Stéphanie Magnet
Keyword(s):  
Particle Size ◽  
Acrylic Acid ◽  
Methyl Methacrylate ◽  
Butyl Acrylate ◽  
Miniemulsion Polymerization ◽  
Radical Copolymerization ◽  
Water Soluble ◽  
Size Distributions ◽  
Particle Size Distributions ◽  
Free Radical Copolymerization

The nitroxide-mediated controlled free-radical copolymerization of styrene (St) and acrylic acid (AA) was used to synthesize a well-defined poly(St30%-co-AA70%) amphiphilic gradient copolymer. The latter proved to be an efficient stabilizer in the 45 wt.-% solids content, batch miniemulsion polymerizations of St and of mixtures of methyl methacrylate/n-butyl acrylate (35/65 w/w). With 2,2´-azobisisobutyronitrile as an oil-soluble initiator, polystyrene latexes with a very narrow particle distribution were obtained, whereas the water-soluble initiator, potassium persulfate, led to broad, multimodal particle size distributions. Such results were explained by the contribution of two nucleation mechanisms: droplet nucleation and homogeneous nucleation. In contrast, the poly(methyl methacrylate-co-n-butyl acrylate) latexes exhibited larger particle size and narrower particle size distributions with persulfate initiator, than the polystyrene latexes.

scholarly journals Modes in the size distributions and neutralization extent of fog-processed ammonium salt aerosols observed at Canadian rural locations

2012 ◽  
Vol 12 (2) ◽  
pp. 5519-5550
Author(s):  
X. H. Yao ◽  
L. Zhang
Keyword(s):  
Ammonium Sulfate ◽  
Ammonium Salt ◽  
Inorganic Ions ◽  
Dominant Mode ◽  
Water Soluble ◽  
Size Distributions ◽  
Minor Mode ◽  
Water Soluble Inorganic Ions ◽  
Acidic Conditions ◽  
A Minor

Abstract. Among the 192 samples of size-segregated water-soluble inorganic ions collected using a Micro-Orifice Uniform Deposit Impactor (MOUDI) at eight rural locations in Canada, ten samples were identified to have gone through fog processing. The supermicron particle modes of ammonium salt aerosols were found to be the fingerprint of fog processed aerosols. However, the patterns and the sizes of the supermicron modes varied with ambient temperature (T) and particle acidity and also differed between inland and coastal locations. Under T > 0 °C condition, fog-processed ammonium salt aerosols were completely neutralized and had a dominant mode at 1–2 μm and a minor mode at 5–10 μm if particles were in neutral condition, and ammonium sulfate was incompletely neutralized and only had a 1–2 μm mode if particles were in acidic conditions. Under T < 0 °C at the coastal site, fog-processed aerosols exhibited a bi-modal size distribution with a dominant mode of incompletely-neutralized ammonium sulfate at about 3 μm and a minor mode of completely-neutralized ammonium sulfate at 8–9 μm. Under T < 0 °C condition at the inland sites, fog-processed ammonium salt aerosols were sometimes completely neutralized and sometimes incompletely neutralized, and the size of the supermicron mode was in the range from 1 to 5 μm. Overall, fog-processed ammonium salt aerosols under T < 0 °C condition were generally distributed at larger size (e.g., 2–5 μm) than those under T > 0 °C condition (e.g., 1–2 μm).

Advances in the Characterization of Particle Size Distributions of Abrasive Particles used in CMP

2007 ◽  
Vol 991 ◽  
Author(s):  
Mungai Kamiti ◽  
Stacey Popadowski ◽  
Edward E. Remsen
Keyword(s):  
Particle Size ◽  
Colloidal Silica ◽  
Particle Diameter ◽  
Water Soluble ◽  
Size Distributions ◽  
Organic Additives ◽  
Particle Size Distributions ◽  
Abrasive Particles ◽  
Theoretical Simulations

ABSTRACTThe use of density gradient stabilized centrifugal sedimentation (disc centrifugation) for the characterization of abrasive particles in CMP slurries is reported. For slurries prepared with ceria and colloidal silica abrasives, the technique is demonstrated as capable of providing highly repeatable analyses of the abrasive's apparent particle size distribution (PSD). The addition of water soluble organic additives to the slurries is shown to produce large shifts in the apparent PSD relative to the PSD of the pure abrasive particles. Particle-additive interactions driving the shift in apparent PSD could not be interpreted with confidence due to the lack of accurate densities for particle-abrasive complexes formed in the slurry. To address this problem, sucrose density gradients prepared using H2O and D2O were tested as spin fluids of different densities to analyze a colloidal silica standard with a narrow PSD. Preliminary results comparing experimental disc centrifuge data with theoretical simulations of the disc sedimentation pattern suggest that this technique can potentially characterize both the particle diameter and density of abrasive particles in a CMP slurry.

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