Laboratory Spectra of Polycyclic Aromatic Hydrocarbon Ions and the Interstellar Extinction Curve

1993 ◽  
Vol 410 ◽  
pp. L127 ◽  
Author(s):  
Wei Lee ◽  
Thomas J. Wdowiak
Keyword(s):  
Polycyclic Aromatic Hydrocarbon ◽  
Aromatic Hydrocarbon ◽  
Interstellar Extinction ◽  
Extinction Curve ◽  
Polycyclic Aromatic

scholarly journals The PAH Hypothesis and the Extinction Curve

1989 ◽  
Vol 135 ◽  
pp. 173-180
Author(s):  
A. Léger ◽  
L. Verstraete ◽  
L. D'Hendecourt ◽  
D. Défourneau ◽  
O. Dutuit ◽  
...  
Keyword(s):  
Polycyclic Aromatic Hydrocarbon ◽  
Aromatic Hydrocarbon ◽  
Extinction Curve ◽  
Interstellar Matter ◽  
Molecular Stability ◽  
Polycyclic Aromatic ◽  
Small Grains

The Polycyclic Aromatic Hydrocarbon (PAH) hypothesis states that a mixture of free PAH molecules is an ubiquitous and abundant component of the interstellar matter. It has been first formulated by Léger and Puget (1984) on the basis of molecular stability that made PAHs good candidates for the very small grains proposed by Sellgren (1984). Then, they obtained strong, although not final, support from spectroscopy.

1,1’-Biaceanthrylene and 2,2'-Biaceanthrylene: Models for Linking Larger Polycyclic Aromatic Hydrocarbons via Five-Membered Rings

2019 ◽  
Author(s):  
Yachu Du ◽  
Kyle Plunkett
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Polycyclic Aromatic Hydrocarbon ◽  
Aromatic Hydrocarbon ◽  
Electronic Properties ◽  
Aromatic Hydrocarbons ◽  
Model Systems ◽  
Redox Potentials ◽  
Dimer Model ◽  
Optical And Electronic Properties ◽  
Polycyclic Aromatic

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>

1,1’-Biaceanthrylene and 2,2'-Biaceanthrylene: Models for Linking Larger Polycyclic Aromatic Hydrocarbons via Five-Membered Rings

2019 ◽  
Author(s):  
Yachu Du ◽  
Kyle Plunkett
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Polycyclic Aromatic Hydrocarbon ◽  
Aromatic Hydrocarbon ◽  
Electronic Properties ◽  
Aromatic Hydrocarbons ◽  
Model Systems ◽  
Redox Potentials ◽  
Dimer Model ◽  
Optical And Electronic Properties ◽  
Polycyclic Aromatic

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>

Karakterisasi Komponen Aktif Asap Cair Cangkang Sawit Hasil Pemurnian

2016 ◽  
Vol 9 (1) ◽  
pp. 64-72
Author(s):  
Fauziati Fauziati ◽  
Eldha Sampepana
Keyword(s):  
Acetic Acid ◽  
Polycyclic Aromatic Hydrocarbon ◽  
Aromatic Hydrocarbon ◽  
Activated Charcoal ◽  
Oil Refining ◽  
Gas Chromatography Mass Spectrometry ◽  
Antioxidant Compounds ◽  
Active Components ◽  
Liquid Smoke ◽  
Polycyclic Aromatic

Palm shell liquid smoke obtained by pyrolysis and redestilasi still produce a pungent smoke flavor and color of yellow to brownish yellow so that the necessary research purification of smoke that can be used as ingredients other than preservatives, such as antiseptic hand wash. The research objective is to reduce the stinging liquid smoke aroma, color is tawny and to identify the characterization of the active components of liquid smoke shell oil refining results in Gas Chromatography Mass Spectrometry (GC-MS). The purification process of liquid smoke with redistilled at a temperature of 2000C and by adding 4.5% zeolite adsorbent made three (3) times the resulting liquid smoke of distillate and residue. Liquid smoke produced from distillate and residue are added activated charcoal as much as 9%, 10.5% and 12%, then stirred with a shaker subsequently allowed to stand for 6 days and 10 days The results of the study showed that liquid smoke purification results of the residue by the addition of activated charcoal as 12% and the time saved for 10 days (A2B2C3) gives flavor and color by 1.94 of 1.84 is odorless, yellowish white color and clarity. While the characteristics of the active components of purification results are predominantly acetic acid and phenol compounds of residues that serve as preservatives, antibacterial and antioxidant compounds while PAH (Polycyclic Aromatic Hydrocarbon), namely tar, benzoperen, gualakol and siringoll (aroma causes) undetectedABSTRAKAsap cair cangkang sawit yang diperoleh melalui proses pirolisis dan redestilasi masih menghasilkan aroma asap menyengat dan warna kuning hingga kuning kecoklatan sehingga diperlukan penelitian pemurnian asap yang dapat digunakan sebagai bahan lain selain pengawet, seperti antiseptik pencuci tangan. Tujuan penelitian adalah  untuk mengurangi aroma asap cair yang menyengat, warna yang masih kuning kecoklatan dan untuk  mengidentifikasi karakterisasi komponen aktif asap cair cangkang sawit hasil pemurnian secara Kromatografi Gas Spektrometri Massa (GC-MS). Proses  pemurnian asap cair dengan  redistilasi pada suhu 2000C dan dengan menambahkan adsorben zeolit 4,5% yang dilakukan sebanyak 3 (tiga) kali  dihasilkan asap cair dari Destilat dan Residu . Asap cair  yang dihasilkan dari destilat dan residu ditambahkan arang aktif sebanyak 9%,10,5% dan 12%  kemudian diaduk dengan shaker selanjutnya didiamkan selama 6 hari dan 10 hari .Hasil penelitian menunjukkan bahwa asap cair hasil pemurnian dari residu dengan penambahan arang aktif sebanyak 12% dan waktu simpan selama 10 hari ( A2B2C3 ) memberikan aroma sebesar 1,94 dan warna sebesar 1,84 adalah tidak berbau ,  warna putih kekuningan dan jernih . Sedangkan  karakteristik  komponen aktif hasil pemurnian yang paling dominan  adalah  senyawa acetic acid dan phenol  dari residu yang berfungsi sebagai bahan pengawet, antibakteri dan antioksidan sedangkan senyawa PAH (Polycyclic Aromatic Hydrocarbon) yaitu tar, benzoperen,  gualakol  dan siringoll ( penyebab aroma ) tidak terdeteksi . Kata kunci : asap cair, cangkang sawit, komponen aktif, pemurnian, redestilasi 

DISCHARGE WATERS: DETERMINATION OF POLYCYCLIC AROMATIC HYDROCARBON (PAH) LEVELS BY A GC-MS/MS METHOD

2015 ◽  
Vol 14 (5) ◽  
pp. 1195-1202 ◽  
Author(s):  
Nadia Crini ◽  
Coline Druart ◽  
Caroline Amiot ◽  
Sophie Gavoille ◽  
Gregorio Crini
Keyword(s):  
Polycyclic Aromatic Hydrocarbon ◽  
Aromatic Hydrocarbon ◽  
Polycyclic Aromatic
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