O2 photoabsorption in the 40 950–41 300 cm−1 region: New Herzberg bands, new absorption lines, and improved spectroscopic data

Optical high-resolution spectroscopic observations of the emission-line star MWC645 are presented. The spectrum exhibits strong variable double-peaked Balmer emission lines as well as low-excitation emission lines of FeII, [FeII], and [OI] which are signatures of the B[e] phenomenon, while lines of helium have not been found. In addition to the emission lines, for the first time we identified absorption lines of neutral metals (e.g., LiI 6708 A, CaI 6717 A, and a number of FeI and TiI lines) that indicate the presence of a cool component in the system. The heliocentric radial velocity measured in our best spectrum was found to be −65.1±1.0 kms −1 for the emission lines and −23.2±0.4 kms −1 for the absorption lines. Using a combination of photometric and spectroscopic data as well as the Gaia EDR3 distance (D=6.5±0.9 kpc), we disentangled the component contributions and estimated their temperatures and luminosities (∼15000 K and ∼4000 K, log L/L ? = 3.8±0.2 and 2.8±0.2 for the hot and cool component, respectively).

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Models of Cataclysmic Variables from Photometric and Spectroscopic Data

International Astronomical Union Colloquium ◽

10.1017/s0252921100073292 ◽

1979 ◽

Vol 46 ◽

pp. 65-74 ◽

Cited By ~ 1

Author(s):

A.C. Fabian ◽

J.E. Pringle ◽

J.A.J. Whelan ◽

J.A. Bailey

Keyword(s):

Spectroscopic Data ◽

Cataclysmic Variables ◽

System Parameters ◽

Dwarf Nova ◽

Spectroscopic Observations ◽

Photometric And Spectroscopic Observations

Abstract.Recent photometric and spectroscopic observations of the dwarf nova system Z Cha are discussed. Methods for constraining the system parameters are applied and the disc emissivity is deduced as a function of radius. Indications are found that the disc shrinks in size with increasing time after outburst.

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Millimetre-wave and infrared spectroscopy of Br13 CN: anharmonic force field of cyanogen bromide from spectroscopic data and ab initio calculations

Molecular Physics ◽

10.1080/00268979709482631 ◽

1997 ◽

Vol 90 (3) ◽

pp. 495-497

Author(s):

CLAUDIO ESPOSTI ◽

FILIPPO TAMASSIA ◽

CRISTINA PUZZARINI ◽

RICCARDO TARRONI ◽

ZDENEK ZELINGER

Keyword(s):

Infrared Spectroscopy ◽

Force Field ◽

Ab Initio Calculations ◽

Ab Initio ◽

Spectroscopic Data ◽

Cyanogen Bromide ◽

Millimetre Wave ◽

Anharmonic Force

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EXPERIMENTAL LINE LIST OF WATER VAPOR ABSORPTION LINES IN THE SPECTRAL RANGES 1850 - 2280 CM AND 2390 - 4000 CM

Proceedings of the 72nd International Symposium on Molecular Spectroscopy ◽

10.15278/isms.2017.tj04 ◽

2017 ◽

Author(s):

Joep Loos ◽

Georg Wagner ◽

Manfred Birk

Keyword(s):

Water Vapor ◽

Absorption Lines ◽

Water Vapor Absorption ◽

Line List ◽

Experimental Line ◽

Vapor Absorption ◽

Spectral Ranges

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Synthesis of Some New Tetracyclic Pyrimidine Derivatives Using Exocyclic α,β-Unsaturated Ketone and Evaluation of Their Antitumor Activities

JOURNAL OF ADVANCES IN CHEMISTRY ◽

10.24297/jac.v12i8.2840 ◽

2016 ◽

Vol 12 (8) ◽

pp. 311-317

Author(s):

Kamelia El-Mahdy

Keyword(s):

Antitumor Activity ◽

Spectroscopic Data ◽

Acid Hydrazide ◽

Chloroacetic Acid ◽

Equimolar Amount ◽

Unsaturated Ketone ◽

Cyanoacetic Acid ◽

Antitumor Activities ◽

Pyrimidine Derivatives ◽

Cyanoacetic Acid Hydrazide

Thiazolopyrimidine 2 was obtained from the reaction of dihydropyrimidinone with chloroacetic acid and benzaldehyde. Thiazolopyrimidine 2 containing an α,β-unsaturated ketonic function [-CH=CH-CO-] has been used as a component of Michael addition with an equimolar amount of dinucleophiles to give a series of novel tetracyclic pyrimidine derivatives. Treatment of thiazolopyrimidine 2 with uracil, aminotriazole, cyanoacetic acid hydrazide, o-phenylenediamine or diaminopyridine afforded the corresponding pyridopyrimidine, triazolopyrimidine, pyrazolone, benzodiazepine and triazepine derivative, respectively. The detailed synthesis, spectroscopic data, and antitumor activity for synthesized compounds were reported.

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Inhibition of Protein Tyrosine Phosphatase 1B by Lutein Derivatives isolated from Mexican Oregano (Lippia graveolens)

Phytothérapie ◽

10.3166/phyto-2018-0074 ◽

2018 ◽

Vol 17 (3) ◽

pp. 134-139

Author(s):

R.M. Perez-Gutierrez

Keyword(s):

Protein Tyrosine Phosphatase ◽

Inhibitory Activity ◽

Spectroscopic Data ◽

Methanol Extract ◽

Tyrosine Phosphatase ◽

Positive Control ◽

Protein Tyrosine Phosphatase 1B ◽

Protein Tyrosine ◽

Ic50 Value ◽

Ic50 Values

Methanol extract from Lippia graveolens (Mexican oregano) was studied in order to identify inhibitory bioactives for protein tyrosine phosphatase 1B (PTP1B). Known flavone as lutein (1), and another flavone glycoside such as lutein-7-o-glucoside (2), 6-hydroxy-lutein-7-ohexoside (3) and lutein-7-o-ramnoide (4) were isolated from methanol extract of aerial parts of the Lippia graveolens. All isolates were identified based on extensive spectroscopic data analysis, including UV, IR, NMR, MS and compared with spectroscopic data previously reported. These flavones were evaluated for PTP1B inhibitory activity. Among them, compounds 1 and 3 displayed potential inhibitory activity against PTP1B with IC50 values of 7.01 ± 1.25 μg/ml and 18.4 μg/ml, respectively. In addition, compound 2 and 4 showed moderate inhibitory activity with an IC50 value of 23.8 ± 6.21 and 67.8 ± 5.80 μg/ml respectively. Among the four compounds, luteolin was found to be the most potent PTP1B inhibitor compared to the positive control ursolic acid, with an IC50 value of 8.12 ± 1.06 μg/ml. These results indicate that flavonoids constituents contained in Lippia graveolens can be considered as a natural source for the treatment of type 2 diabetes.

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