• Journal of Environmental Health Sciences
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• v.34 no.6
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• pp.439-445
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• 2008

The feasibility study for the application of the removal and mineralization of Rhodamine B (RhB) was performed in a batch electrochemical reactor. The electro/UV process was consisted of DSA (dimensionally stable anode) electrode and UV-C or ozone lamp. The experimental results showed that RhB removal by the ozone lamp was higher than that of the UV-C lamp. Optimum current of the electro/UV process was 1 A. The electrochemical, UV and electro/UV process could completely degrade RhB, while a prolonged treatment was necessary to reach a high level RhB mineralization. It was observed that RhB removal in electro/UV process is similar to the sum of the UV and electrolytic decolorization. However, it was found that the COD of RhB could be degraded more efficiently by the electro/UV process (90.2 %) than the sum of the two individual oxidation processes [UV (19.7%) and electrolytic process (50.8%)]. A synergetic effect was demonstrated between the UV and electrolysis.

• Korean Journal of Optics and Photonics
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• v.4 no.3
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• pp.338-346
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• 1993

The rotational reorientation times of rhodamine 6G molecule were measured using a time-correlated single photon counting method. To explain the deviation of observed rotational reorientation times in alcohol solvents from the prediction of hydrodynamic model, the contribution of dielectric friction was considered. And the values of transition dipole moments in ground and excited states were estimated through the dielectric friction and the static spectroscopic data.

• Bulletin of the Korean Chemical Society
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• v.29 no.3
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• pp.571-574
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• 2008

The well-known Cu2+-selective chemodosimetric behavior of rhodamine B hydrazide was successfully switched to selectivity for Hg2+. The fluorescence signaling is remarkably selective toward Hg2+ ions compared to other common biologically and environmentally important metal ions, including Cu2+ ions. The detection limit was 0.2 mM in an acetate-buffered aqueous 10% methanol solution at pH 5. The OFF-ON type of signaling is due to the selective Hg2+-induced hydrolysis of the lactam ring of the hydrazide as has been reported for the standard Cu2+-signaling process of the same compound. A simple change in medium resulted in clear switching of selective signaling from Cu2+ to Hg2+, which extends the applicability of the easily accessible hydrazide derivative.

• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1061-1064
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• 2013

A known $Hg^{2+}$ selective rhodamine B derivatised probe 1 was reinvestigated as a colorimetric and fluorescent probe for $Cu^{2+}$ through changing the applied solvent media. Probe 1 exhibited good selectivity and sensitivity to $Cu^{2+}$ in $CH_3CN-H_2O$ (7:3, v/v, HEPES 10 mM, pH 7.0) solution with a detection limit of $9.74{\times}10^{-7}$ M. The $Cu^{2+}$ sensing event was proved to be irreversible through hydrolysis of 1 to release rhodamine B.

• Textile Coloration and Finishing
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• v.24 no.4
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• pp.233-238
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• 2012

The opto-functional materials have been developed as a promising research topic toward the end uses for optical materials and applications. The attractive area in this part was the design of sensor molecules for detecting harmful environmental factors. These harmful factors impart undesired effects on wide range of chemical and biological phenomenon. In this context, many researchers have studied luminescence chemosensor materials. These sensor molecules showed optical signals such as color or fluorescence change by detecting harmful environmental factors. In this study, the novel fluorescence chemosensor 1 has been designed and synthesized through reaction of rhodamine 6g hydrazide and 2-hydroxy-1-naphthaldehyde. The chemosensor 1 had been analyzed by UV-Vis and fluorescence spectrophotometer. We found that this chemosensor 1 has 'off-on' and dual type sensing properties toward $Cu^{2+}$ and $Mg^{2+}$.

• Journal of Korean Society on Water Environment
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• v.23 no.2
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• pp.274-280
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• 2007

The photochemical decolorization of Rhodamine B (RhB) in water has been carried out by photo-Fenton process. The effect of applied $H_2O_2$, $Fe^{2+}$ dose, solution pH and UV dose have been studied. The influence of constituent processes of photo-Fenton such as UV, $H_2O_2$ and Fenton has been investigated. Comparison of RhB removal was made between the photo-Fenton and $UV/H_2O_2$ process. The results obtained showed that the optimum dosage of $Fe^{2+}$ and $H_2O_2$ were 0.0031 mmol and 0.625 mol, respectively. pH 3 is found to be the optimum pH of for photo-Fenton process. pH and UV dose strongly influenced the decolorization of RhB in photo-Fenton process. The photo-Fenton and $UV/H_2O_2$ processes showed similar decolorization and seem to be appropriate for the decolorization of dye wastewater.

• Journal of Sericultural and Entomological Science
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• v.35 no.1
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• pp.73-76
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• 1993

Adding a non-fluorescent dye, Rhodamine-B, to the adult diet of uzi fly, Exorista bombysis (Louis) has shown to be a useful method for marking the eggs for flight range experiments. The method is timesaving and the dye is safe to handle and the marked eggs are easy to detect. Files fed on the diet added with dye did not have much negative effect on adult mortality and fecundity, but egg hatchability was affected.

• Clean Technology
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• v.21 no.2
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• pp.102-107
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• 2015

Rhodamine dyes are widely used as fluorescent probes because of their excellent photophysical properties, such as high extinction coefficients, excellent quantum yields, great photostability, relatively long emission wavelengths. A great synthetic effort has been focused on developing efficient and practical procedures to prepare rhodamine derivatives, because for most applications the probe must be covalently linked to another (bio)molecule or surface. Sulforhodamine B is one of the most used rhodamine dyes for this purpose, because it carries two sulfoxy functions which can be easily utilized for binding with other molecules. Recently, we needed an expedient, practical synthesis of sulforhodamine derivatives. We found the existing procedure for obtaining those compounds unsatisfactory, particularly, with the cyclization process of the dihydroxytriarylmethane (1) to produce the corresponding xanthene derivative (2). We report here our findings, which represent modification of the existing literature procedure and provide access to the corresponding xanthene derivative (2) in a high yield. Use of methanol as a co-solvent was found quite effective to prohibit the water molecule produced during the cyclization reaction from retro-cyclizing back to the starting dihydroxytriarylmethane and the yield of the cyclization was increased (up to 84% from less than 20%). The reaction temperature was significantly lowered (80 vs. 135 ℃). Thus, the reaction proceeds in a higher yield and energy-saving manner where the use of reactants and the production of chemical wastes is minimized.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1777-1780
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• 2011

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.741-744
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• 2011