| 11. |
|
|
| 12. |
- Akselsson, Roland, et al.
(författare)
-
Mass Calibration in PIXE Analysis
- 1977
-
Ingår i: X-Ray Fluorescence Analysis of Environmental Samples. - 0250401347 ; , s. 175-180
-
Bokkapitel (refereegranskat)
|
|
| 13. |
- Akselsson, Roland, et al.
(författare)
-
Particle Size Distribution and Human Respiratory Deposition of Trace Metals in Indoor Work Environments
- 1976
-
Ingår i: Annals of Occupational Hygiene. - : Oxford University Press (OUP). - 1475-3162. ; 19:3-4, s. 225-238
-
Tidskriftsartikel (refereegranskat)abstract
- Respiratory response to inhalation of fine particles has been investigated for the aerosol generated by welding. Particles were sampled using a pair of 5-stage cascade impactors operating at 1 l./min flow rate. The subject exhaled into one impactor through an air ballast arrangement, and the other impactor simultaneously sampled the surrounding air. Particle size fractions were analyzed for principal elemental constituents from sulphur to lead using proton induced X-ray emission, PIXE. The results indicated a complex respiratory response, including both increase in particle size due to exposure to high humidity in the respiratory tract and deposition of particles during inhalation. The response was found to be different for the element group Mn, Cr, Fe, Ni compared to the group K, Ca, Ti by observing the associations among the elements as a function of particle size in the inhaled and exhaled aerosol. However, for respiratory deposition efficiency alone in all runs averaged together, no systematic differences between the different elements are demonstrated at the 99 % confidence level.
|
|
| 14. |
|
|
| 15. |
- Akselsson, Roland, et al.
(författare)
-
PIXE Analysis Research in Lund
- 1979
-
Ingår i: IEEE Transactions on Nuclear Science. - 0018-9499. ; NS-26:1, s. 1358-1362
-
Tidskriftsartikel (refereegranskat)abstract
- Protons or a-particles from a 3 MV tandem Pelletron are used to induce characteristic x-rays, which are detected by a Si(Li)-detector. To optimize the quality and speed of data taking we use an absorber with a hole, pile-up rejection and on-demand beam. Forty samples may be entered simultaneously into the vacuum, and their positioning is operated by pushbuttons. The system is prepared for minicomputer steering. PIXE is combined with analysis of backscattered particles and in some cases γ-ray detection from a 19F(p,αγ) 160-reaction. At different stages of development we have a bent-chrystal spectrometer, microbeam and facilities to extract the beam from vacuum. In the introduction of PIXE to applied fields, it is important, that physicists take part in identifying, planning and performing suitable projects e.g. experiments where rapid multielemental analysis of many samples is crucial. In Lund we investigate the elemental composition of size-fractionated airborne particles from work environments and ambient air. The objectives are then to learn about sources, transport and deposition of particles and to contribute to the understanding of relations between exposure and health effects. We are also developing procedures for trace elemental analysis of water. Detection limits in the range of 0.1 ppb have been demonstrated. In other projects in progress biological and mineralogical samples are analysed.
|
|
| 16. |
|
|
| 17. |
|
|
| 18. |
|
|
| 19. |
- Akselsson, Roland, et al.
(författare)
-
Proton Scattering for Analysis of Atmospheric Particulate Matter
- 1975
-
Ingår i: Bulletin of the American Physical Society Ser II. ; 20
-
Tidskriftsartikel (refereegranskat)abstract
- Proton scattering has been applied to the problem of elemental quantitative analysis of air particulate matter. Elements up through chlorine may be resolved using 16 MeV protons incident upon targets up to about 1 mg/cm2 in thickness. Using the FSU Super FM Tandem Accelerator and a large area solid state proton detector, an analysis can be performed in several minutes. Combination of this technique with proton induced X-ray emission analysis provides a means of quantitative analysis for all elements. These accelerator based methods are being applied to studies of the composition of air particulate matter in diverse locations such as St. Louis, Mo.; Los Angeles, Ca.; several cities in Florida; and Bermuda.
|
|
| 20. |
|
|
