scholarly journals Examination of Different Inks Available in Ethiopia Using VSC 8000, U.V-Visible Spectrophotometer and TLC: Study of Their Discrimination Potential

2019 ◽  
pp. 66-69
Author(s):  
Natinael Mekonnen
Keyword(s):  
Crystal Violet ◽  
Rhodamine B ◽  
Medical Records ◽  
Rhodamine 6G ◽  
Detailed Examination ◽  
Chemical Compositions ◽  
Ink Analysis ◽  
Coloring Agents ◽  
Non Destructive

Ink analysis is the most challenging and commonly encountered problem faced by a forensic chemist. Ink present on documents such as contracts, cheques, testaments, medical records, to quote just a few, is regularly contested for its authentication. In this paper, we have examined the various inks available in Ethiopia (speciallyArba Minch) using chromatography and spectroscopy methods, and have tried to decode the chemical compositions of these inks emphasizing on coloring agents followed by evaluating the discrimination potential of these techniques. This study is the first kind of detailed examination of inks available in Ethiopia as there is no precedence literature to it. It was found out that the examined ink samples can be divided into five major groups having mainly rhodamine b, rhodamine 6G and crystal violet as coloring agents. The TLC and UV-Vis techniques although discriminate inks samples to a little better extent than VSC, but VSC should be preferred due to its non-destructive nature.

Luminescence Quenching of Rhodamines by Cyclooctatetraene

1987 ◽  
Vol 42 (9) ◽  
pp. 1009-1013 ◽  
Author(s):  
P. Targowski ◽  
B. Ziętek ◽  
A. Bączyński
Keyword(s):  
Rhodamine B ◽  
Rate Constants ◽  
Internal Conversion ◽  
Rhodamine 6G ◽  
Second Order ◽  
Luminescence Quenching ◽  
Intersystem Crossing ◽  
Order Rate ◽  
Quenching Process

Cyclooctatetraene (COT) as a quencher of fluorescence of a series of Rhodamine solutions was studied. The second order rate constants for the quenching process of Rhodamine 110, Rhodamine 19 pchl., Rhodamine 6G pchl., Rhodamine 6G, Tetramethylrhodamine, Rhodamine B and Rhodamine 3B pchl. are given. It was found that COT enhances rather intersystem crossing than internal conversion.

Manipulating Energy Transfer Processes between Rhodamine 6G and Rhodamine B in Different Mesoporous Hosts

2007 ◽  
Vol 111 (14) ◽  
pp. 5541-5548 ◽  
Author(s):  
Lingzhi Wang ◽  
Yuanlin Liu ◽  
Feng Chen ◽  
Jinlong Zhang ◽  
Masakazu Anpo
Keyword(s):  
Energy Transfer ◽  
Rhodamine B ◽  
Rhodamine 6G ◽  
Transfer Processes

Facile Synthesis of Boron Organic Polymers for Efficient Removal and Separation of Methylene Blue, Rhodamine B, and Rhodamine 6G

2018 ◽  
Vol 6 (12) ◽  
pp. 16777-16787 ◽  
Author(s):  
Xue Zhao ◽  
Dan Wang ◽  
Changjun Xiang ◽  
Fulin Zhang ◽  
Luchang Liu ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Rhodamine B ◽  
Rhodamine 6G ◽  
Organic Polymers ◽  
Efficient Removal ◽  
Facile Synthesis

scholarly journals Toward an Accurate Spectrophotometric Evaluation of the Efficiencies of Photocatalysts in Processes Involving Their Separation Using Nylon Membranes

Catalysts ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 576
Author(s):  
Halema Al-Kandari ◽  
Peter Kasak ◽  
Ahmed Mohamed ◽  
Shekhah Al-Kandari ◽  
Dusan Chorvat Jr. ◽  
...  
Keyword(s):  
Rhodamine B ◽  
Significant Interaction ◽  
Rhodamine 6G ◽  
Solid Particles ◽  
Phenol Red ◽  
Model Compounds ◽  
Filtration Process ◽  
Nylon Membrane ◽  
Membrane Filters ◽  
Photocatalytic Reactors

Many works include the use of nylon membranes to separate the solid particles of photocatalysts from the photocatalytic reactors, before using spectrophotometers to evaluate the catalysts’ performance in the photocatalytic degradation of many pollutants. This might lead to significant errors due to the adsorption of some pollutants within the structure of the membranes during the filtration process used to separate the solid particles of the photocatalysts to get a clear filtrate. This, consequently, leads to incorrect calculations, which in turn are translated into false high photocatalytic efficiencies of the used catalysts. In this work, the authors study the interaction between nylon membrane filters and five different model compounds—phenol red, methylene blue, rhodamine B, rhodamine 6G, and phenol. The study reveals a significant interaction between the nylon membranes and both rhodamine B and phenol red.

Influence of laser and material parameters on two photon absorption in Rhodamine B and Rhodamine 6G solutions in MeOH

Optik ◽  
2019 ◽  
Vol 183 ◽  
pp. 835-841 ◽  
Author(s):  
Rabia Ahmad ◽  
M. Shahid Rafique ◽  
Ali Ajami ◽  
Shazia Bashir ◽  
Wolfgang Husinsky ◽  
...  
Keyword(s):  
Rhodamine B ◽  
Rhodamine 6G ◽  
Photon Absorption ◽  
Two Photon Absorption ◽  
Material Parameters ◽  
Two Photon

scholarly journals An External Energy Independent WO3/MoCl5 Nano-Sized Catalyst for the Superior Degradation of Crystal Violet and Rhodamine B Dye

Catalysts ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 642 ◽  
Author(s):  
Dongin Kim ◽  
Geonwoo Kim ◽  
Hyeonbin Bae ◽  
Eunwoo Kim ◽  
Byunghyun Moon ◽  
...  
Keyword(s):  
Crystal Violet ◽  
Rhodamine B ◽  
Degradation Product ◽  
Reaction Rate ◽  
Advanced Oxidation Process ◽  
Reaction Rate Constant ◽  
Thermal Method ◽  
External Energy ◽  
Superior Result ◽  
Reaction Rate Increase

In this study, the synthesis of a novel catalyst WO3/MoCl5 was carried out by the thermal method. The method gave an entirely different product compared to previous studies that doped Mo on the surface of semiconductor metal oxides. The degradation reaction of crystal violet (CV) and rhodamine B (RB) dye were done without any energy source. The results showed an incomparably superior result for degradation, with a reaction rate constant of 1.74 s−1 for 30 ppm CV, 1.08 s−1 for 30 ppm RB, and a higher value than 1 s−1 for both cases of 50 ppm dye solution. To the author’s knowledge, this catalyst has the highest reaction rate compared to other studies that targeted CV and RB, with an immense reaction rate increase of more than 100 times. Reusability of the three trials was verified, and the only process required was washing the catalyst after the reaction. One of the drawbacks of the advanced oxidation process (AOP), which has a degradation percent limit, has been solved, since 100% mineralization of the dye was available using this catalyst. FT-IR spectroscopy revealed that W-O-Mo linkage was successfully processed while Mo-Cl linkage has retained. 1H-NMR spectroscopy results confirmed that the degradation product of the dye treated by simple MoCl5 and WO3/MoCl5 was different. Deep inspection of specific regions of NMR fields gave necessary information about the degradation product using WO3/MoCl5.

Sign in / Sign up

Export Citation Format

Share Document