scholarly journals The Environments of the Massive Star Clusters in the Carina Nebula

2002 ◽  
Vol 207 ◽  
pp. 129-131
Author(s):  
Kate Brooks ◽  
Jill Rathborne ◽  
Michael Burton

We have imaged over an extensive field the 3.29-μm emission from the Carina Nebula. This emission arises from polycyclic aromatic hydrocarbons which are excellent tracers of photodissociation regions. The results emphasis the two very different environments of the massive star clusters of the nebula, Trumpler 14 and 16.

1978 ◽  
Vol 35 (5) ◽  
pp. 528-535 ◽  
Author(s):  
P. D. Keizer ◽  
T. P. Ahern ◽  
J. Dale ◽  
J. H. Vandermeulen

The Arrow spill in February 1970 heavily oiled approximately one half of the 600 km shoreline of Chedabucto Bay, Nova Scotia. An extensive field survey and chemical analysis of sediment samples for aliphatic and polycyclic aromatic hydrocarbons identified only a few locations where Arrow Bunker C remained in the intertidal and sublittoral sediments. The upper intertidal zones of Rabbit, Crichton, and Durell islands remain covered with an oil and sediment mixture of a "pavement-like" consistency. Several areas showed visual and chemical evidence of recent spills during the survey period. All sublittoral sediment samples contained hydrocarbons of petroleum origin. The distribution of the most highly contaminated sublittoral sediments suggests either reentry of stranded oil into the water column and into the sublittoral sediments or contamination from shipping and fishing vessels. Concentrations in the sublittoral sediments are below those found toxic to benthic organisms. An estimation of the amount of Bunker C remaining in Chedabucto Bay is impossible due to the patchy distribution, contributions of more recent spills, and the absence of adequate control sites. Key words: Bunker C, oil spill, Chedabucto Bay, gas–liquid chromatography, fluorescence spectroscopy, n-alkanes, polycyclic aromatic hydrocarbons


2019 ◽  
Vol 64 (1) ◽  
pp. 55-67
Author(s):  
Vlad Pӑnescu ◽  
◽  
Mihaela Cӑtӑlina Herghelegiu ◽  
Sorin Pop ◽  
Mircea Anton ◽  
...  

2019 ◽  
Author(s):  
Yachu Du ◽  
Kyle Plunkett

We show that polycyclic aromatic hydrocarbon (PAH) chromophores that are linked between two five-membered rings can access planarized structures with reduced optical gaps and redox potentials. Two aceanthrylene chromophores were connected into dimer model systems with the chromophores either projected outward (2,2’-biaceanthrylene) or inward (1,1’-biaceanthrylene) and the optical and electronic properties were compared. Only the planar 2,2’-biaceanthrylene system showed significant reductions of the optical gaps (1 eV) and redox potentials in relation to the aceanthrylene monomer.<br>


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