Size-resolved, quantitative evaluation of the magnetic mineralogy of airborne brake-wear particulate emissions

2021 ◽  
pp. 117808
Author(s):  
Tomasz Gonet ◽  
Barbara A. Maher ◽  
Ilona Nyirő-Kósa ◽  
Mihály Pósfai ◽  
Miroslav Vaculík ◽  
...  
Author(s):  
R. Stevenson

A study has been made of the morphology and crystallography of particulate emissions from indirect injection diesel engines. This particulate matter consists substantially of carbon (although hydrocarbons can be extracted with solvents). Samples were collected in a diluted exhaust stream on amorphous carbon films and examined in a JEM-200C electron microscope operated in the TEM mode with an accelerating voltage of 200 KV.The morphology of the diesel particles, as shown in Fig. 1, markedly resembles carbon blacks and consists of an agglomeration of quasispherical subunits arranged in chains or clusters. Only limited changes in morphology were observed as the number of subunits in the particle increased (although larger particles tended to be more cluster-like than the extended chain shown in Fig. 1). However, a dramatic effect of the number of subunits was observed on the character of the diffraction pattern. Smaller particles yielded a diffraction pattern consisting of very diffuse rings typical of turbostratic carbon; the diffraction patterns from the larger particles, however, although qualitatively similar, exhibited much sharper and less diffuse ring patterns.


Physica ◽  
1952 ◽  
Vol 18 (2) ◽  
pp. 1147-1150
Author(s):  
D MAEDER ◽  
V WINTERSTEIGER

2017 ◽  
Author(s):  
Francesca Serra ◽  
Andrea Spoto ◽  
Marta Ghisi ◽  
Giulio Vidotto

2000 ◽  
Vol 05 (2) ◽  
pp. 129-138
Author(s):  
Robert A. Luhm ◽  
Daniel B. Bellissimo ◽  
Arejas J. Uzgiris ◽  
William R. Drobyski ◽  
Martin J. Hessner

1987 ◽  
Vol 26 (06) ◽  
pp. 234-240 ◽  
Author(s):  
H. Stirner ◽  
J. Dahl ◽  
R. Uebis ◽  
E. Kleinhans ◽  
M. Biedermann ◽  
...  

ROI-based polar maps (33 ROIs) were employed to evaluate quantitatively stress/rest myocardial 201TI SPECT in 108 patients with angiographically proven coronary heart disease (CHD) in comparison with 30 controls. Sensitivity in detecting a CHD with stenoses of > 50% of luminal diameter was determined versus normal regional values (± 2.5 SD) employing vitality (VI) and wash-out corrected redistribution (RD). The method was evaluated referring to the severity of the disease, to the number of ROIs displaying changes [(a) 1 ROI, (b) >2 ROIs], to validity of VI, RD or a combination thereof, and for specificity. Wash-out values were found to depend on degree of stress individually achieved and thus were not used as a threshold criterion. Sensitivity in supply areas with old myocardial infarctions was 95% (a) and 86% (b), resp. With no infarction, it was 96% (a) and 79% (b), resp. VI in stenosis > 75% was more sensitive than RD. However, combined evaluation of VI and RD yielded sensitivities from 91-100% (a) and 77-94% (b), resp. for different main supply areas. In stenosis < 50% with normal VI, RD was positive in 18-31 %. Specificity turned out to be 91 % (a) and 97% (b), resp. We conclude that the method presented is reliable to quantify numerically 201TI kinetics in myocardial SPECT, aimed at detecting and describing CHD.


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