Validation of PM2.5 Concentrations Based on Finnish Emission—Source-Receptor Scenario Model

Author(s):  
Ville-Veikko Paunu ◽  
Niko Karvosenoja ◽  
Kaarle Kupiainen ◽  
Leena Kangas ◽  
Mikko Savolahti ◽  
...  
Author(s):  
A. V. Crewe ◽  
J. Wall ◽  
L. M. Welter

A scanning microscope using a field emission source has been described elsewhere. This microscope has now been improved by replacing the single magnetic lens with a high quality lens of the type described by Ruska. This lens has a focal length of 1 mm and a spherical aberration coefficient of 0.5 mm. The final spot size, and therefore the microscope resolution, is limited by the aberration of this lens to about 6 Å.The lens has been constructed very carefully, maintaining a tolerance of + 1 μ on all critical surfaces. The gun is prealigned on the lens to form a compact unit. The only mechanical adjustments are those which control the specimen and the tip positions. The microscope can be used in two modes. With the lens off and the gun focused on the specimen, the resolution is 250 Å over an undistorted field of view of 2 mm. With the lens on,the resolution is 20 Å or better over a field of view of 40 microns. The magnification can be accurately varied by attenuating the raster current.


Author(s):  
W. T. Pike

With the advent of crystal growth techniques which enable device structure control at the atomic level has arrived a need to determine the crystal structure at a commensurate scale. In particular, in epitaxial lattice mismatched multilayers, it is of prime importance to know the lattice parameter, and hence strain, in individual layers in order to explain the novel electronic behavior of such structures. In this work higher order Laue zone (holz) lines in the convergent beam microdiffraction patterns from a thermal emission transmission electron microscope (TEM) have been used to measure lattice parameters to an accuracy of a few parts in a thousand from nanometer areas of material.Although the use of CBM to measure strain using a dedicated field emission scanning transmission electron microscope has already been demonstrated, the recording of the diffraction pattern at the required resolution involves specialized instrumentation. In this work, a Topcon 002B TEM with a thermal emission source with condenser-objective (CO) electron optics is used.


2004 ◽  
Vol 62 (1-6) ◽  
pp. 167-173
Author(s):  
A. O. Kulyukin ◽  
S. N. Panychev ◽  
N. T. Khakimov
Keyword(s):  

2016 ◽  
Vol 2016 (5) ◽  
pp. 5860-5864
Author(s):  
John L Willis ◽  
Robert Bastian ◽  
Bill Brower ◽  
Christine DeBarbadillo ◽  
Sudhir Murthy ◽  
...  
Keyword(s):  

Author(s):  
Kohei Sakata ◽  
Yoshio Takahashi ◽  
Shotaro Takano ◽  
Atsushi Matsuki ◽  
Aya Sakaguchi ◽  
...  

Author(s):  
Donatella Pomata ◽  
Patrizia Di Filippo ◽  
Carmela Riccardi ◽  
Federica Castellani ◽  
Giulia Simonetti ◽  
...  

In the last years, many studies have focused on risk assessment of exposure of workers to airborne particulate matter (PM). Several studies indicate a strong correlation between PM and adverse health outcomes, as a function of particle size. In the last years, the study of atmospheric particulate matter has focused more on particles less than 10 μm or 2.5 μm in diameter; however, recent studies identify in particles less than 0.1 μm the main responsibility for negative cardiovascular effects. The present paper deals with the determination of 66 organic compounds belonging to six different classes of persistent organic pollutants (POPs) in the ultrafine, fine and coarse fractions of PM (PM < 0.1 µm; 0.1 < PM < 2.5 µm and 2.5 < PM < 10 µm) collected in three outdoor workplaces and in an urban outdoor area. Data obtained were analyzed with principal component analysis (PCA), in order to underline possible correlation between sites and classes of pollutants and characteristic emission sources. Emission source studies are, in fact, a valuable tool for both identifying the type of emission source and estimating the strength of each contamination source, as useful indicator of environment healthiness. Moreover, both carcinogenic and non-carcinogenic risks were determined in order to estimate human health risk associated to study sites. Risk analysis was carried out evaluating the contribution of pollutant distribution in PM size fractions for all the sites. The results highlighted significant differences between the sites and specific sources of pollutants related to work activities were identified. In all the sites and for all the size fractions of PM both carcinogenic and non-carcinogenic risk values were below acceptable and safe levels of risks recommended by the regulatory agencies.


2019 ◽  
Vol 83 (1) ◽  
pp. 43-52 ◽  
Author(s):  
Felix Leaman ◽  
Steffen Hinderer ◽  
Ralph Baltes ◽  
Elisabeth Clausen ◽  
Brian Rieckhoff ◽  
...  

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