Progress in Multidimensional Particle Characterization

1991 ◽

Vol 49 ◽

pp. 896-897

Author(s):

Marylyn Bennett-Lilley ◽

Thomas T.H. Fu ◽

David D. Yin ◽

R. Allen Bowling

Keyword(s):

Chemical Vapor ◽

Device Performance ◽

Particle Characterization ◽

Particle Generation ◽

Tungsten Hexafluoride ◽

Homogeneous Particle ◽

Multiple Levels ◽

Circuit Density ◽

Sources Of Contamination

Chemical Vapor Deposition (CVD) tungsten metallization is used to increase VLSI device performance due to its low resistivity, and improved reliability over other metallization schemes. Because of its conformal nature as a blanket film, CVD-W has been adapted to multiple levels of metal which increases circuit density. It has been used to fabricate 16 MBIT DRAM technology in a manufacturing environment, and is the metallization for 64 MBIT DRAM technology currently under development. In this work, we investigate some sources of contamination. One possible source of contamination is impurities in the feed tungsten hexafluoride (WF6) gas. Another is particle generation from the various reactor components. Another generation source is homogeneous particle generation of particles from the WF6 gas itself. The purpose of this work is to investigate and analyze CVD-W process-generated particles, and establish a particle characterization methodology.

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METHOD FOR LUBRICATED SLIDING WEAR PARTICLE CHARACTERIZATION

10.26678/abcm.cobem2019.cob2019-2239 ◽

2019 ◽

Author(s):

Alessandro Augusto Olimpio Ferreira Vittorino ◽

Túlio Alves Rodrigues ◽

Marco Aurélio Freitas Santos Júnior ◽

Washington Martins da Silva Jr.

Keyword(s):

Sliding Wear ◽

Wear Particle ◽

Particle Characterization ◽

Lubricated Sliding

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Development of a Field Deployable Firebrand Flux and Condition Measurement System

Fire Technology ◽

10.1007/s10694-020-01074-x ◽

2020 ◽

Author(s):

Simone Zen ◽

Jan C. Thomas ◽

Eric V. Mueller ◽

Bhisham Dhurandher ◽

Michael Gallagher ◽

...

Keyword(s):

Imaging Techniques ◽

Time History ◽

Infrared Camera ◽

Thermal Conditions ◽

Particle Characterization ◽

Fire Dynamics ◽

Rate Of Spread ◽

New Instrument ◽

History Of

AbstractA new instrument to quantify firebrand dynamics during fires with particular focus on those associated with the Wildland-Urban Interface (WUI) has been developed. During WUI fires, firebrands can ignite spot fires, which can rapidly increase the rate of spread (ROS) of the fire, provide a mechanism by which the fire can pass over firebreaks and are the leading cause of structure ignitions. Despite this key role in driving wildfire dynamics and hazards, difficulties in collecting firebrands in the field and preserving their physical condition (e.g. dimensions and temperature) have limited the development of knowledge of firebrand dynamics. In this work we present a new, field-deployable diagnostic tool, an emberometer, designed to provide measurement of firebrand fluxes and information on both the geometry and the thermal conditions of firebrands immediately before deposition by combining a visual and infrared camera. A series of laboratory experiments were conducted to calibrate and validate the developed imaging techniques. The emberometer was then deployed in the field to explore firebrand fluxes and particle conditions for a range of fire intensities in natural pine forest environments. In addition to firebrand particle characterization, field observations with the emberometer enabled detailed time history of deposition (i.e. firebrand flux) relative to concurrent in situ fire behaviour observations. We highlight that deposition was characterised by intense, short duration “showers” that can be reasonably associated to spikes in the average fire line intensity. The results presented illustrate the potential use of an emberometer in studying firebrand and spot fire dynamics.

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Effects of Size and Surface Properties of Nanodiamonds on the Immunogenicity of Plant-Based H5 Protein of A/H5N1 Virus in Mice

Nanomaterials ◽

10.3390/nano11061597 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1597

Author(s):

Thuong Thi Ho ◽

Van Thi Pham ◽

Tra Thi Nguyen ◽

Vy Thai Trinh ◽

Tram Vi ◽

...

Keyword(s):

High Pressure ◽

Neutralizing Antibodies ◽

H5n1 Virus ◽

Vaccine Development ◽

Particle Characterization ◽

Innovative Strategy ◽

Specific Igg ◽

Positively Charged

Nanodiamond (ND) has recently emerged as a potential nanomaterial for nanovaccine development. Here, a plant-based haemagglutinin protein (H5.c2) of A/H5N1 virus was conjugated with detonation NDs (DND) of 3.7 nm in diameter (ND4), and high-pressure and high-temperature (HPHT) oxidative NDs of ~40–70 nm (ND40) and ~100–250 nm (ND100) in diameter. Our results revealed that the surface charge, but not the size of NDs, is crucial to the protein conjugation, as well as the in vitro and in vivo behaviors of H5.c2:ND conjugates. Positively charged ND4 does not effectively form stable conjugates with H5.c2, and has no impact on the immunogenicity of the protein both in vitro and in vivo. In contrast, the negatively oxidized NDs (ND40 and ND100) are excellent protein antigen carriers. When compared to free H5.c2, H5.c2:ND40, and H5.c2:ND100 conjugates are highly immunogenic with hemagglutination titers that are both 16 times higher than that of the free H5.c2 protein. Notably, H5.c2:ND40 and H5.c2:ND100 conjugates induce over 3-folds stronger production of both H5.c2-specific-IgG and neutralizing antibodies against A/H5N1 than free H5.c2 in mice. These findings support the innovative strategy of using negatively oxidized ND particles as novel antigen carriers for vaccine development, while also highlighting the importance of particle characterization before use.

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