Luminescence and Laser Properties of the 10-Phenyl-9-acetoxyanthracene Derivatives

Absorption and fluorescence spectra, fluorescence quantum yield and decay time have been measured for eight new 10-phenyl-9-acetoxyanthracene derivatives. It is found that the strength of the absorption transition is independent of the phenyl and anthracene substitution, whereas the strength of the fluorescence transition depends more on the functional groups substituted in the anthracene ring then in the phenyl ring. The loss of mirror symmetry between the absorption and emission spectra and the large values of the Stokes shift suggest that, due to perturbation of the functional groups, the molecular geometries of the S0 and S*1 states are different.The investigated compounds show laser action. The relative value of the absorption threshold power, the gain spectra and the lasing region have been determined. It is found that the amplified spontaneous emission and gain spectra depend on the interaction of the substituted phenyl ring with the π-electrons of the anthracene ring

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Synthesis, Spectroscopic Properties of Bis-Boc-L-Alanine Modiﬁed 1,8-Naphthyridine Ligand Induced by Hg2+

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1089.121 ◽

2015 ◽

Vol 1089 ◽

pp. 121-124

Author(s):

Gao Zhang Gou ◽

Bo Zhou ◽

Ling Shi ◽

Xian Lan Chen ◽

Na Wu ◽

...

Keyword(s):

Heavy Metal ◽

Mirror Symmetry ◽

Heavy Metal Ions ◽

Fluorescence Spectra ◽

Electronic Absorption Spectra ◽

Emission Spectra ◽

Spectroscopic Properties ◽

Ion Source ◽

Absorption And Fluorescence Spectra ◽

Comprehensive Study

One Bis-Boc-L-alanine-1,8-naphthyridine ligand containing amino acid by amido bond named 2,7-Bis-Boc-L-alanine-1,8-naphthyridine (L1) was synthesized and characterized. And there absorption and fluorescence spectra in methanol is presented. It exhibits electronic absorption spectra with λmax at about 340 nm, which can be tentatively assigned to π→π* transition. The emission spectra of L1 in CH3OH shows a mirror symmetry peak with λmax at about 375 nm. Then, the comprehensive study of spectroscopic properties upon titration of L1 with heavy metal ions as ion source in CH3OH was investigated.

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Influence of Functional Groups on the Photophysical Properties of 1-(4-Methylsulfonyl Phenyl)-3-(4-n, n Dimethyl (amino Phenyl)-2-Propen-1-One Chalcone as Laser Dye

Asian Journal of Physical and Chemical Sciences ◽

10.9734/ajopacs/2021/v9i130128 ◽

2021 ◽

pp. 22-29

Author(s):

M. F. Attia ◽

Abdelrahman A. Elbadawi ◽

K. H. Ibnaouf ◽

A. O. Elzupir

Keyword(s):

Functional Groups ◽

Optical Materials ◽

Fluorescence Spectra ◽

Laser Excitation ◽

Photophysical Properties ◽

Stokes Shift ◽

Wavelength Band ◽

Fluorescence Characteristics ◽

Pulse Laser Excitation ◽

Synthesized Materials

In this work, 1-(4-methylsulfonyl phenyl)-3-(4-N, N dimethyl amino phenyl)-2-propen-1-one (MSPPP) chalcone was synthesized and examined as optical materials. The absorption and fluorescence characteristics of MSPPP chalcone were recorded in ten different solvents. The influence of functional groups (FG) and solvents on their photophysical properties were investigated. These include absorption, fluorescence, stokes shift, and amplified spontaneous emission (ASE). The absorption spectra of MSPPP showed a wavelength band in the range 404 - 427 nm, whereas the fluorescence spectra exhibited a band at 473 - 533 nm. The FGs and solvents had an adorable effect on the optical properties of the synthesized materials. ASE was observed under pump pulse laser excitation, and the wavelengths were attuned from 511 to 548 nm.

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The Synthesis and Electroluminescence Properties of 4-Benzofuranyl-1,8-Naphthalimide Derivatives

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.557-559.1031 ◽

2012 ◽

Vol 557-559 ◽

pp. 1031-1036 ◽

Cited By ~ 4

Author(s):

Jian Xin Yang ◽

Xiang Hui Wang

Keyword(s):

Absorption Spectra ◽

Fluorescence Spectra ◽

Cycloaddition Reaction ◽

Emission Spectra ◽

Luminescent Properties ◽

Quantum Yields ◽

Absorption And Fluorescence Spectra ◽

Maximum Brightness ◽

Maximum Emission ◽

Mild Conditions

A series of fluorescence compounds, 4-benzofuranyl-1,8-naphthalimides, were prepared through cycloaddition reaction from 4-ethynyl-1,8-naphthalimides and o-iodophenols which catalyzed by a Pd(PPh3)2Cl2 / CuI system under mild conditions. The intermediate material, 4-ethynyl-1,8- naphthalimide, was synthesized from 4-bromo-1,8- naphthalimide and trimethylsilyl- acetylene. The absorption and fluorescence spectra of 4-benzofuranyl-1,8- naphthalimides were studied and the quantum yields were measured. The maximum UV/vis absorption spectra were in the range of 375-400 nm and the maximum emission spectra were in the range of 470-510 nm. The electro- luminescent properties were also mensurated through a doped electroluminescent device which contains 1% 1,8-naphthalimides and 99% CBP (4,4'-N,N'-dicarbazole-biphenyl), It’s shown the maximum brightness reached 3700 cd/ m2 at 22.5V.

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Luminescent Hybrid Materials Based on Curcumin Derivatives Embedded in Palygorskite

Materiale Plastice ◽

10.37358/mp.18.1.4964 ◽

2018 ◽

Vol 55 (1) ◽

pp. 63-67

Author(s):

Monica Florentina Raduly ◽

Valentin Raditoiu ◽

Alina Raditoiu ◽

Luminita Eugenia Wagner ◽

Viorica Amariutei ◽

...

Keyword(s):

Hybrid Materials ◽

Fluorescence Spectra ◽

Fluorescence Emission ◽

Emission Spectra ◽

Hydroxyl Groups ◽

Fluorescent Properties ◽

Fluorescence Emission Spectra ◽

Curcumin Derivatives ◽

Absorption Studies ◽

Inorganic Matrix

The seven curcumin derivatives were deposited on palygorskite in order to obtain hybrid materials. The fluorescence emission spectra of the obtained materials show a decrease in fluorescence intensity relative to the respective dyes, due to the environments around the dyestuff molecules created in the host matrices. Absorption studies show the best adsorption on the inorganic matrix, for the compounds with the hydroxyl groups. Correlating fluorescence spectra of hybrid materials with the results for absorption spectra of the dyes adsorbtion on the surface of the clay lead to the conclusion that a high percentage of the adsorbed dye had the effect of fluorescence quenching. Thus, it was confirmed that the fluorescent properties of hybrid materials depend on the interactions established between the fluorescent dyestuff and the inorganic network.

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Spectral Properties of Hybrid of Rhodamine (6G) Dyes Doped Epoxy Resin Dissolved in Chloroform

Baghdad Science Journal ◽

10.21123/bsj.2019.16.3(suppl.).0764 ◽

2019 ◽

Vol 16 (3(Suppl.)) ◽

pp. 0764 ◽

Cited By ~ 1

Author(s):

Al-Hamdani Et al.

Keyword(s):

Epoxy Resin ◽

Quantum Efficiency ◽

Fluorescence Spectra ◽

Room Temperature ◽

Rhodamine 6G ◽

Energy Gap ◽

Radiative Lifetime ◽

Stokes Shift ◽

Fluorescence Emission ◽

Absorption And Fluorescence Spectra

The research is dealing with the absorption and fluorescence spectra for the hybrid of an Epoxy Resin doped with organic dye Rhodamine (R6G) of different concentrations (5*10-6, 5*10-5, 1*10-5, 1*10-4, 5*10-4) Mol/ℓ at room temperature. The Quantum efficiency Qfm, the rate of fluorescence emission Kfm (s-1), the non-radiative lifetime τfm (s), fluorescence lifetime τf and the Stokes shift were calculated. Also the energy gap (Eg) for each dye concentration was evaluated. The results showed that the maximum quantum efficiency 62 % and maximum stokes shift 96 nm was obtained in dye concentration 5*10-6 and 1*10-4. The energy gap ranges between 1.066 eV to 1.128 eV depending proportionally on the dye concentrations.

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Semi-blind sparse affine spectral unmixing of autofluorescence-contaminated micrographs

Bioinformatics ◽

10.1093/bioinformatics/btz674 ◽

2019 ◽

Vol 36 (3) ◽

pp. 910-917 ◽

Cited By ~ 1

Author(s):

Blair J Rossetti ◽

Steven A Wilbert ◽

Jessica L Mark Welch ◽

Gary G Borisy ◽

James G Nagy

Keyword(s):

Fluorescence Spectra ◽

Nonnegative Matrix ◽

Emission Spectra ◽

Factorization Method ◽

Reconstruction Error ◽

Spectral Unmixing ◽

Great Promise ◽

Background Fluorescence ◽

Pixel Location ◽

Reference Images

Abstract Motivation Spectral unmixing methods attempt to determine the concentrations of different fluorophores present at each pixel location in an image by analyzing a set of measured emission spectra. Unmixing algorithms have shown great promise for applications where samples contain many fluorescent labels; however, existing methods perform poorly when confronted with autofluorescence-contaminated images. Results We propose an unmixing algorithm designed to separate fluorophores with overlapping emission spectra from contamination by autofluorescence and background fluorescence. First, we formally define a generalization of the linear mixing model, called the affine mixture model (AMM), that specifically accounts for background fluorescence. Second, we use the AMM to derive an affine nonnegative matrix factorization method for estimating fluorophore endmember spectra from reference images. Lastly, we propose a semi-blind sparse affine spectral unmixing (SSASU) algorithm that uses knowledge of the estimated endmembers to learn the autofluorescence and background fluorescence spectra on a per-image basis. When unmixing real-world spectral images contaminated by autofluorescence, SSASU greatly improved proportion indeterminacy as compared to existing methods for a given relative reconstruction error. Availability and implementation The source code used for this paper was written in Julia and is available with the test data at https://github.com/brossetti/ssasu.

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Influence of pH on the Absorption and Fluorescence Spectra of 6,7-Dihydroxycoumarin in Aqueous Solution

Zeitschrift für Naturforschung A ◽

10.1515/zna-1982-0311 ◽

1982 ◽

Vol 37 (3) ◽

pp. 262-265 ◽

Cited By ~ 7

Author(s):

Jerzy Grzywacz ◽

Stanisława Taszner

Keyword(s):

Aqueous Solution ◽

Fluorescence Spectra ◽

Singlet State ◽

Ph Value ◽

Emission Spectra ◽

Excited Singlet ◽

Acid Base ◽

Wide Ph Range ◽

Ph Range ◽

Influence Of Ph

Abstract Absorption and emission spectra of 6,7-dihydroxycoumarin [6,7-DHC] in aqueous solution over a wide pH range are reported. The absorption spectra proved to be strongly sensitive to the pH-value of the solution, whereas the emission spectra change in this range only insignificantly. An interpretation is attempted on the basis of the differences of the acid-base properties of the 6,7-DHC molecule in its ground and excited singlet state. For this purpose the pKa's and pKax's values have been calculated. It has been stated that in the excited state the phototautomer form is very unlikely.

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Engineering difference of band structure between mirror symmetrical adsorption and antisymmetrical adsorption of the identical group on a graphene sheet

The European Physical Journal Applied Physics ◽

10.1051/epjap/2019180301 ◽

2019 ◽

Vol 85 (3) ◽

pp. 30101

Author(s):

Xinyue Zhang ◽

Qingsong Huang

Keyword(s):

Band Structure ◽

Electric Field ◽

Band Gap ◽

Graphene Sheet ◽

Functional Groups ◽

Mirror Symmetry ◽

Dominant Factor ◽

Bonding State ◽

Adsorption Sites ◽

Continuous Tuning

Symmetry of adsorption site is the key to control the graphene band gap. When the adsorption sites change from mirror-symmetry adsorption (MSA) to mirror antisymmetric adsorption (MAA) position, the bandgap change (BC) exhibits two opposite tendencies. Therefore, a standard was developed to determine the type of band gap modification of graphene. When BC is negative, the bonding state between the adsorbent and graphene was the dominant factor. When BC is positive, the built-in electric field becomes dominated. Continuous tuning of the band gap can be achieved by adsorbing the appropriate functional groups. Our findings set the standard for determining the type of band gap modification and open the way for controllable adjustment of graphene band gap.

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The Electric Dipole Moments of Methine Dyes – Comparison of Experimental Results with Theoretical Predictions

Zeitschrift für Naturforschung A ◽

10.1515/zna-1982-0907 ◽

1982 ◽

Vol 37 (9) ◽

pp. 1024-1026

Author(s):

Z. Salamon ◽

A. Skibiński ◽

K. Celnik

Keyword(s):

Dipole Moments ◽

Stokes Shift ◽

Emission Spectra ◽

Solvent Polarity ◽

Electronic Charge ◽

Excited Singlet ◽

Nonpolar Solvents ◽

Singlet States ◽

Theoretical Predictions ◽

Excited Singlet States

Abstract Absorption and emission spectra of methine dyes in polar and nonpolar solvents were measured. From the Stokes shift as a function of solvent polarity the dipole moments of excited singlet states have been estimated and compared with the quantum chemical predictions. Also the π-electronic charge distribution in the ground and first excited singlet electronic states and bond orders of the dyes were calculated. All investigated methines showed an increase in dipole moment upon excitation to the first excited emitting state.

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