scholarly journals The high charge fraction of flame-generated particles in the size range below 3 nm measured by enhanced particle detectors

2017 ◽  
Vol 176 ◽  
pp. 72-80 ◽  
Author(s):  
Yang Wang ◽  
Juha Kangasluoma ◽  
Michel Attoui ◽  
Jiaxi Fang ◽  
Heikki Junninen ◽  
...  
Keyword(s):  
Size Range ◽  
Particle Detectors ◽  
High Charge ◽  
Charge Fraction

Microtomy of spherical Al2O3 powders

1983 ◽  
Vol 41 ◽  
pp. 74-75
Author(s):  
E.J. Jenkins ◽  
D.S. Tucker ◽  
J.J. Hren
Keyword(s):  
Thin Film ◽  
Size Range ◽  
Particle Aggregation ◽  
Ion Milling ◽  
Thin Sections ◽  
Α Phase ◽  
Convenient Means ◽  
Van Der Waals Attraction ◽  
Negative Feature ◽  
Film Substrate

The size range of mineral and ceramic particles of one to a few microns is awkward to prepare for examination by TEM. Electrons can be transmitted through smaller particles directly and larger particles can be thinned by crushing and dispersion onto a substrate or by embedding in a film followed by ion milling. Attempts at dispersion onto a thin film substrate often result in particle aggregation by van der Waals attraction. In the present work we studied 1-10 μm diameter Al2O3 spheres which were transformed from the amprphous state to the stable α phase.After the appropriate heat treatment, the spherical powders were embedded in as high a density as practicable in a hard EPON, and then microtomed into thin sections. There are several advantages to this method. Obviously, this is a rapid and convenient means to study the microstructure of serial slices. EDS, ELS, and diffraction studies are also considerably more informative. Furthermore, confidence in sampling reliability is considerably enhanced. The major negative feature is some distortion of the microstructure inherent to the microtoming operation; however, this appears to have been surprisingly small. The details of the method and some typical results follow.

Microdiffraction Patterns of Small Metallic Particles II; Theoretical Analysis

1982 ◽  
Vol 40 ◽  
pp. 668-669
Author(s):  
A. Gómez ◽  
P. Schabes-Retchkiman ◽  
M. José-Yacamán ◽  
T. Ocaña
Keyword(s):  
Experimental Data ◽  
Electron Diffraction ◽  
Theoretical Analysis ◽  
Size Range ◽  
Dynamical Theory ◽  
Metallic Particles ◽  
Splitting Effect

The splitting effect that is observed in microdiffraction pat-terns of small metallic particles in the size range 50-500 Å can be understood using the dynamical theory of electron diffraction for the case of a crystal containing a finite wedge. For the experimental data we refer to part I of this work in these proceedings.

Electron Microscopy of the Shape of Small Metal Particles

1977 ◽  
Vol 35 ◽  
pp. 300-301
Author(s):  
M. Jose Yacaman
Keyword(s):  
Electron Microscopy ◽  
Metal Particle ◽  
Field Experiments ◽  
Size Range ◽  
Dark Field ◽  
Metal Particles ◽  
Bragg Condition ◽  
Crystal Particle ◽  
Small Metal Particle ◽  
Small Metal Particles

In the Study of small metal particles the shape is a very Important parameter. Using electron microscopy Ino and Owaga(l) have studied the shape of twinned particles of gold. In that work electron diffraction and contrast (dark field) experiments were used to produce models of a crystal particle. In this work we report a method which can give direct information about the shape of an small metal particle in the amstrong- size range with high resolution. The diffraction pattern of a sample containing small metal particles contains in general several systematic and non- systematic reflections and a two-beam condition can not be used in practice. However a N-beam condition produces a reduced extinction distance. On the other hand if a beam is out of the bragg condition the effective extinction distance is even more reduced.

Freeze-dried dispersions for automated SEM analysis of individual submicron airborne particulates

1992 ◽  
Vol 50 (1) ◽  
pp. 408-409
Author(s):  
Karen A. Katrinak ◽  
David W. Brekke ◽  
John P. Hurley
Keyword(s):  
Air Pollutants ◽  
Size Range ◽  
Sem Analysis ◽  
Individual Particle ◽  
Chemical Data ◽  
Particle Analysis ◽  
Bulk Analysis ◽  
Airborne Particulates ◽  
Freeze Dried ◽  
Individual Particle Analysis

Individual-particle analysis is well established as an alternative to bulk analysis of airborne particulates. It yields size and chemical data on a particle-by-particle basis, information that is critical in predicting the behavior of air pollutants. Individual-particle analysis is especially important for particles with diameter < 1 μm, because particles in this size range have a disproportionately large effect on atmospheric visibility and health.

Electron Microscopy in the Study of Natural Phytoplankton Assemblages

1985 ◽  
Vol 43 ◽  
pp. 620-623
Author(s):  
Linda Sicko-Goad
Keyword(s):  
Electron Microscopy ◽  
Aquatic Environment ◽  
Size Range ◽  
Physical Parameters ◽  
Specific Information ◽  
Phytoplankton Assemblages ◽  
Phytoplankton Productivity ◽  
Ecosystem Effects ◽  
Time Of Year ◽  
Species Specific

Although the use of electron microscopy and its varied methodologies is not usually associated with ecological studies, the types of species specific information that can be generated by these techniques are often quite useful in predicting long-term ecosystem effects. The utility of these techniques is especially apparent when one considers both the size range of particles found in the aquatic environment and the complexity of the phytoplankton assemblages.The size range and character of organisms found in the aquatic environment are dependent upon a variety of physical parameters that include sampling depth, location, and time of year. In the winter months, all the Laurentian Great Lakes are uniformly mixed and homothermous in the range of 1.1 to 1.7°C. During this time phytoplankton productivity is quite low.

381. Sampling Efficiencies of Three Personal Aerosol Samplers within and Beyond the Inhalable Particle Size Range

2001 ◽  
Author(s):  
V. Aizenberg ◽  
P. Baron ◽  
K. Choe ◽  
S. Grinshpun ◽  
K. Willeke
Keyword(s):  
Particle Size ◽  
Size Range ◽  
Particle Size Range

ACCUMULATION OF PLASTIC FRAGMENTS AND MICROPLASTICS ON THE BEACHES IN THE SOUTH-EAST BALTIC SEA

2017 ◽  
Author(s):  
Lilia Khatmullina ◽  
Lilia Khatmullina ◽  
Elena Esiukova ◽  
Elena Esiukova
Keyword(s):  
Baltic Sea ◽  
Size Range ◽  
Anthropogenic Pollution ◽  
The South ◽  
The Baltic Sea ◽  
Quantitative Distribution ◽  
Sediment Sampling ◽  
Beach Sediments ◽  
Kaliningrad Region ◽  
The Baltic

The sediment sampling from different areas of the beaches in the south-eastern part of the Baltic Sea (in Kaliningrad region) was executed for the purpose of studying the quantitative and qualitative composition of the microplastics particles (range 0.5-5 mm). Preference is given to those beaches that are exposed to maximum anthropogenic pollution. From June, 2015 to January, 2016, there were 14 expeditions along the coastline of the Baltic Sea (in Kaliningrad region) to collect experimental materials. The majority of samples were collected on the most recent flotsam deposited at “wracklines”, in the supralittoral zone. The primary examination of those samples revealed the presence of abundant microplastic particles of the required size range (0.5-5 mm). Quantitative distribution of microplastics in beach sediments was obtained in milligrams per gram of sediment and milligrams per m2: on average 0.05-2.89 (mg per gram of sediment) and 370-7330 (mg per m2), accordingly.

Clogging in Irrigation Systems Reusing Pond Effluents and its Prevention

1987 ◽  
Vol 19 (12) ◽  
pp. 323-328 ◽  
Author(s):  
A. Adin
Keyword(s):  
Size Range ◽  
Small Scale ◽  
Main Obstacle ◽  
Reservoir Systems ◽  
Deep Reservoir ◽  
Particulate Removal ◽  
Oxidation Ponds ◽  
Surface Filtration ◽  
Granular Filtration ◽  
Low Rate

The clogging of emitters, orifices or laterals has turned out to be the main obstacle for further use of low rate applicators in wastewater irrigation. Granular filtration and screen filtration were studied and compared for particulate removal using small-scale pilot experiments. The removal ratio of particles larger than 10 µm in direct granular filtration was relatively large while smaller particles showed little removal. Particles in the 10-60µm size range were removed by 40–50 percent in depth and by 80 percent when surface filtration prevailed. Screen filters removed only 1–2 percent of the material but this was sufficient to cause their clogging. A release of particles from the screen into the effluent was observed, resulting in greater number of larger particles and thus greater clogging potential down the irrigation line. Deep-bed granular coarse media filters may serve for the control of particle size in effluents of oxidation ponds - deep reservoir systems while the conventional strainers are less recommended for this purpose.

Sign in / Sign up

Export Citation Format

Share Document