Mass absorption indices of various types of natural aerosol particles in the infrared

1975 ◽  
Vol 14 (12) ◽  
pp. 2851 ◽  
Author(s):  
Klaus Fischer
Keyword(s):  
Aerosol Particles ◽  
Mass Absorption ◽  
Natural Aerosol

Contact nucleation of ice by natural aerosol particles

1976 ◽  
Vol 7 (1) ◽  
pp. 1-4 ◽  
Author(s):  
J. Rosinski ◽  
C.T. Nagamoto
Keyword(s):  
Aerosol Particles ◽  
Natural Aerosol

scholarly journals An overview of the Amazonian Aerosol Characterization Experiment 2008 (AMAZE-08)

2010 ◽  
Vol 10 (7) ◽  
pp. 18139-18195 ◽  
Author(s):  
S. T. Martin ◽  
M. O. Andreae ◽  
D. Althausen ◽  
P. Artaxo ◽  
H. Baars ◽  
...  
Keyword(s):  
Organic Material ◽  
Large Scale ◽  
Amazon Basin ◽  
Particle Number ◽  
Aerosol Particles ◽  
Regional Climate ◽  
Scale Production ◽  
Cloud Activation ◽  
Aerosol Characterization ◽  
Natural Aerosol

Abstract. The Amazon Basin provides an excellent environment for studying the sources, transformations, and properties of natural aerosol particles and the resulting links between biological processes and climate. With this framework in mind, the Amazonian Aerosol Characterization Experiment (AMAZE-08), carried out from 7 February to 14 March 2008 during the wet season in the central Amazon Basin, sought to understand the formation, transformations, and cloud-forming properties of fine- and coarse-mode biogenic aerosol particles, especially as related to their effects on cloud activation and regional climate. Special foci included (1) the production mechanisms of secondary organic components at a pristine continental site, including the factors regulating their temporal variability, and (2) predicting and understanding the cloud-forming properties of biogenic particles at such a site. In this overview paper, the field site and the instrumentation employed during the campaign are introduced. Observations and findings are reported, including the large-scale context for the campaign, especially as provided by satellite observations. New findings presented include: (i) a particle number-diameter distribution from 10 nm to 10 μm that is representative of the pristine tropical rain forest and recommended for model use; (ii) the absence of substantial quantities of primary biological particles in the submicron mode as evidenced by mass spectral characterization; (iii) the large-scale production of secondary organic material; (iv) insights into the chemical and physical properties of the particles as revealed by thermodenuder-induced changes in the particle number-diameter distributions and mass spectra; and (v) comparisons of ground-based predictions and satellite-based observations of hydrometeor phase in clouds. A main finding of AMAZE-08 is the dominance of secondary organic material as particle components. The results presented here provide mechanistic insight and quantitative parameters that can serve to increase the accuracy of models of the formation, transformations, and cloud-forming properties of biogenic natural aerosol particles, especially as related to their effects on cloud activation and regional climate.

scholarly journals An overview of the Amazonian Aerosol Characterization Experiment 2008 (AMAZE-08)

2010 ◽  
Vol 10 (23) ◽  
pp. 11415-11438 ◽  
Author(s):  
S. T. Martin ◽  
M. O. Andreae ◽  
D. Althausen ◽  
P. Artaxo ◽  
H. Baars ◽  
...  
Keyword(s):  
Organic Material ◽  
Large Scale ◽  
Amazon Basin ◽  
Particle Number ◽  
Aerosol Particles ◽  
Regional Climate ◽  
Scale Production ◽  
Cloud Activation ◽  
Aerosol Characterization ◽  
Natural Aerosol

Abstract. The Amazon Basin provides an excellent environment for studying the sources, transformations, and properties of natural aerosol particles and the resulting links between biological processes and climate. With this framework in mind, the Amazonian Aerosol Characterization Experiment (AMAZE-08), carried out from 7 February to 14 March 2008 during the wet season in the central Amazon Basin, sought to understand the formation, transformations, and cloud-forming properties of fine- and coarse-mode biogenic aerosol particles, especially as related to their effects on cloud activation and regional climate. Special foci included (1) the production mechanisms of secondary organic components at a pristine continental site, including the factors regulating their temporal variability, and (2) predicting and understanding the cloud-forming properties of biogenic particles at such a site. In this overview paper, the field site and the instrumentation employed during the campaign are introduced. Observations and findings are reported, including the large-scale context for the campaign, especially as provided by satellite observations. New findings presented include: (i) a particle number-diameter distribution from 10 nm to 10 μm that is representative of the pristine tropical rain forest and recommended for model use; (ii) the absence of substantial quantities of primary biological particles in the submicron mode as evidenced by mass spectral characterization; (iii) the large-scale production of secondary organic material; (iv) insights into the chemical and physical properties of the particles as revealed by thermodenuder-induced changes in the particle number-diameter distributions and mass spectra; and (v) comparisons of ground-based predictions and satellite-based observations of hydrometeor phase in clouds. A main finding of AMAZE-08 is the dominance of secondary organic material as particle components. The results presented here provide mechanistic insight and quantitative parameters that can serve to increase the accuracy of models of the formation, transformations, and cloud-forming properties of biogenic natural aerosol particles, especially as related to their effects on cloud activation and regional climate.

Reactivity of polycyclic aromatic compounds (PAHs, NPAHs and OPAHs) adsorbed on natural aerosol particles exposed to atmospheric oxidants

2012 ◽  
Vol 61 ◽  
pp. 15-22 ◽  
Author(s):  
Johany Ringuet ◽  
Alexandre Albinet ◽  
Eva Leoz-Garziandia ◽  
Hélène Budzinski ◽  
Eric Villenave
Keyword(s):  
Aromatic Compounds ◽  
Aerosol Particles ◽  
Polycyclic Aromatic Compounds ◽  
Polycyclic Aromatic ◽  
Natural Aerosol

Gaussian ϕ(ρz) curves: Comparison with other models

1990 ◽  
Vol 48 (2) ◽  
pp. 192-193
Author(s):  
Alberto Riveros ◽  
Gustavo Castellano
Keyword(s):  
Good Description ◽  
Bulk Sample ◽  
Incident Electron Energy ◽  
Power Mean ◽  
General Shape ◽  
Ionization Cross ◽  
X Ray ◽  
Mass Absorption ◽  
Absorption Correction ◽  
Image Position

X ray characteristic intensity Ii , emerging from element i in a bulk sample irradiated with an electron beam may be obtained throughwhere the function ϕi(ρz) is the distribution of ionizations for element i with the mass depth ρz, ψ is the take-off angle and μi the mass absorption coefficient to the radiation of element i.A number of models has been proposed for ϕ(ρz), involving several features concerning the interaction of electrons with matter, e.g. ionization cross section, stopping power, mean ionization potential, electron backscattering, mass absorption coefficients (MAC’s). Several expressions have been developed for these parameters, on which the accuracy of the correction procedures depends.A great number of experimental data and Monte Carlo simulations show that the general shape of ϕ(ρz) curves remains substantially the same when changing the incident electron energy or the sample material. These variables appear in the parameters involved in the expressions for ϕ(ρz). A good description of this function will produce an adequate combined atomic number and absorption correction.

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