Amader

Di Valentin, C. Freccero, M. Zanaletti, C. Sarzi-Amade, M. o-Quinone methide as alkylating agent of nitrogen, oxygen, and sulfur nucleophiles. The role of H-bonding and solvent effects on the reactivity through a DFT computational study, j. Am. Chem. Soc. 2001, 123, 8366-8377. 

Freccero, M. Gandolfi, R. Sarzi-Amade, M. Selectivity of purine alkylation by a quinone methide. Kinetic or thermodynamic control J. Org. Chem. 2003, 68, 6411-6423. 

Animal model Am specie s Exposure Exposure concentration3 Aerosol AMAD (pm GSD) Lung deposition (percent of dose) Lung retention or absorption half-time15 Reference... 

Animal Am Exposure AMAD Lung deposition absorption ... 

AMAD = activity median aerodynamic GSD = geometric standard deviation... 

Predictions based on the model have been compared to observed time courses for lung, liver, and skeletal americium burden in dogs that inhaled americium oxide (Mewhinney and Griffith 1983). Data on lung retention for four humans who accidentally inhaled americium were also compared to model predictions. The empirical observations fell within predicted retention patterns for particle sizes (AMAD) 0.5 and 1.8 im (Mewhinney and Griffith 1983). 

Activity Median Aerodynamic Diameter (AMAD)—The diameter of a unit-density sphere with the same terminal settling velocity in air as that of the aerosol particle whose activity is the median for the entire size distribution of the aerosol. 

Amad, M. H. Cech, N. B. Jackson, G. S. Enke, C. G. Importance of gas-phase proton affinities in determining the electrospray ionization response for analytes and solvents. I. Mass Spectrom. 2000,35,784-789. 

Aerodynamic Size Distributions of Naturally-Radioactive Aerosols. Measurements of radionuclide distributions using cascade impactors indicate that Be-7 and Pb-210 are associated with larger aerosols than Pb-212 and Pb-214 (Robig et al., 1980 Papastefanou and Bondietti, 1986). Measurements of Pb-210 associations over oceans indicated activity median aerodynamic diameters (AMAD) near 0.6 pm (Sanak et al., 1981). The impactor measurements of Moore et al. (1980) on Pb-210, Bi-210, and Sr-90 sizes in continental air indicated that about 80% of the activity from all three nuclides was associated with aerosols below 0.3 pm. That work also determined that the mean age of aerosol Pb-210 was about a week. Knuth et al. (1983) compared Pb-210 and stable Pb sizes at a continental location and found that 78% of the Pb-210 found below 1.73 pm was smaller than 0.58 pm. Young (1974) reported that the most of the Be-7 in the atmosphere was associated with submicron aerosols. 

The Pb-214 AMADs, determined with the LPI, varied from 0.10 to 0.37 um (mean value, 0.16 um). For Pb-212, they varied from 0.07 to 0.245 um (mean value 0.12 pm) (Papastefanou and Bondietti, 1986). These AMAD calculations were made assuming lognormal distributions and using the manufacturer s cutoff points. An abbreviated version of these results is presented in Table II. 

Pb-212 vs S0%- LPI Distributions. Figure 3 presents a summary of the average Pb-212 AMADs and SOj MADs (mass median aerodynamic diameters) determined from a series of LPI measurements made during the period January to October, 1985. The Pb-212 data were derived from collections made at the same time as S0jj and from measurements made to compare Pb-212 vs Pb-214. The mean aerodynamic diameter of Pb-212 was about three times smaller than SoJ . Much less sulfate was found in the aerosol fraction below 0.08 um, compared with Pb-212. While Pb-212 was largely absent above 0.52 um, about 20% of the SoJ occurred above this size. 

Table II. Summary of Mean Monthly Activity Median Aerodynamic Diameters (AMAD) and Geometric Standard Deviations (tfg) of Radon and Thoron Daughter Size Distributions in Ambient Aerosols...

Pb-210 and the Cosmogenic Radionuclides. We noted earlier that our measurements of Pb-214 were really measurements of Po-214 decay, that is, the production of Pb-210. The mean AMAD of these measurements was about 0.16 um, with the AMAD of Pb-210 predicted to be 0.18 um after recoil. However, the summer AMAD of Pb-210, after aging in the atmosphere for about a week (Moore et al., 1980), was closer to 0.4 um, indicating that Pb-210 s AMAD approximately doubles during its lifetime in the atmosphere. The limited measurements reported here suggest that the AMAD of Pb-210 is smaller in winter than summer, possibly reflecting differences in aerosol growth rates. The summer measurements were also not different from simultaneous SoJ measurements. 

The aerodynamic size distributions of Pb-214, Pb-212, Pb-210, Be-7, P-32, S-35-SoJ , and stable SO4 were measured using cascade impactors. Pb-212 and Pb-214, measured by alpha spectroscopy, were largely associated with aerosols small than 0.52 11m. Based on over 46 low-pressure impactor measurements, the mean activity median aerodynamic diameter (AMAD) of Pb-212 was found to be 0.13 11m, while for Pb-214 the AMAD was larger—0.16 lim. The slightly larger size of Pb-214, confirmed with operationally different impactors, was attributed to a-recoil-driven redistribution of Pb-214 following decay of aerosol-associated Po-218. A recoil model was presented that explained this redistribution. Low-pressure impactor measurements indicated that the mass median aerodynamic diameter of SoJ ... 

Animal species Aerosol form AMAD (ftfn) Age at Exposure No. animals Deposition Initial lung Reference... 

Beagle dog inhalation "CeCl, AMAD t.5-2,4 ion a, 1.6-2.1 13-16 mos 70 life span (in progress) death, bone marrow aplasia and pancytopenia, radiation pneumonitis, pulmonary fibrosis, hepatic necrosis 11/48 Yes pulmonary adenoma, bronchtogenic adenocarcinoma 3/48 Yes he man- Yes giocarcinoma osteosarcoma, 6/48 leukemia 3/34 (primary) Benjamin et al. (1972b 1976c) Merickel et al. (1978)... 

Beagle dog inhalation l44Ce in fused aluminosilicate particles AMAD 1.6-2.2 pm o 1.3-1,6 3 mos 54 life span (in progress) pulmonary fibrosis, radiation pneumonitis, congenital heart failure 5/12 Yes hemangiosarcoma 4/12 Yes No hemangiosar- coma 1/12 Hanicka-Rebar (1978)... 

Beegle dog inhalation, 44Ce in fused aluminosilicate particles AMAD 1.6-2.3 pm o, 1.3—1.6 8-10.5 yr 54 life span (in progress) radiation pneumonitis, cong. heart failure, fibrosis 17/33 Yes bronchiolo alveolar carcinoma 3/33 No No Hahn et of. (1978b)... 

Beagle dog inhalation M4CeOi AMAD 0.3-3 pm adult 10 5 yr radiation pneumonitis, pulmonary fibrosis No No No Stuart et al. (1964) Stuart and Gaven (1967) Stuart and Gaven (1968)... 

Syrian hamster inhalation CeOa, 860°C AMAD 1-2 p 26 d 84 d 340 d 7 7 5 life span (in progress) radiation pneumonitis, pulmonary fibrosis No No No Hobbs et al. (1975)... 

Mouse repeated inhalation CeO, 850°C AMAD 1.2-1.5pm o, 1.4-1.7 8-10 wkfl 820 life span radiation pneumonitis Yes 14/92 pulmon aden. (7)k pulmon sarc. (1) pulmon care. (6) No No Lundgren et al. (1975)... 

Rat intratracheal AMAD 1.35-1.42 pm o, 1.7-1.9 "CeCli, pH 3 — 130 edema, fibrosis, proliferation of alveolar Lining cells, thickening of interal- No No No (1974) Korolev (1969a ... 

Freccero M, Gandolh R, Sarzi-Amade M, Rastelli A. J. Chem. Soc., Perkin Trans. 2 1998 2413. 

Gandolfi R, Amade MS, Rastelli A, Bagatti M, Montanari D. Tetrahedron Lett. 1996 37 517. 

M90 Automatic Agent Detector (AMAD) An automatic nerve and mustard agent detector that detects agents in vapor form. It transmits an alarm by radio to a central alarm unit. It is currently used in the Air Force. 

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