Showing papers on "Brilliant green published in 2011"

In Situ Preparation of Highly Fluorescent Dyes upon Photoirradiation

Abstract: Photoswitchable or photoactivatable fluorescent dyes are potentially applicable to ultrahigh density optical memory media as well as super-resolution fluorescence imaging when the dyes are highly fluorescent and have large absorption coefficients. Here, we report on highly fluorescent photochromic dyes, which are initially nonluminous in solution under irradiation with visible light but activated to emit green or red fluorescence upon irradiation with ultraviolet (UV) light. The dyes 5a–9a are sulfone derivatives of 1,2-bis(2-ethyl-6-phenyl(or thienyl)-1-benzothiophen-3-yl)perfluorocyclopentene. It was found that substitution of phenyl or thiophene rings at 6 and 6′ positions of the benzothiophene-1,1-dioxide groups is effective to increase the fluorescence quantum yields of the closed-ring isomers over 0.7 and absorption coefficients over 4 × 104 M–1 cm–1. The phenyl-substituted derivatives 5a–7a undergo photocyclization reactions to produce yellow closed-ring isomers 5b–7b, which emit brilliant green fl...

Removal of cationic dyes from aqueous solutions with poly ( N -isopropylacrylamide- co -itaconic acid) hydrogels

Abstract: In this study, N-isopropylacrylamide-based temperature and pH-sensitive hydrogels were synthesized by free radical polymerization for removal of cationic dyes from aqueous solutions. For this purpose, N-isopropylacrylamide was copolymerized with various amounts of sodium salt of itaconic acid in the presence of crosslinking agent (N,N-methylene bisacrylamide). The chemical structures of hydrogels were characterized by FT-IR analysis. In order to investigate swelling properties of the hydrogels, water absorption (swelling) and shrinking (deswelling) kinetics, the equilibrium swelling ratios in water and different pH buffer solutions, and the temperature dependent swelling ratios were determined. Then, their adsorption properties such as adsorption capacities, kinetics, isotherms were investigated in case of their usage in removal of Safranine T (ST), Brilliant Green (BG), and Brilliant Cresyl Blue (BCB) aqueous solutions. According to adsorbed dye amount, the adsorption capacities are followed the order BG > ST ≅ BCB. In addition, the results indicated that the pseudo-second-order kinetic model fitted better than the data obtained from pseudo-first-order model for the adsorption of all dyes onto hydrogels. Furthermore, according to effect of the initial dye concentration findings, it is concluded that, Freundlich isotherm explains the adsorption better than Langmuir isotherm.

Adsorption of Brilliant Green from Aqueous Solutions onto Crosslinked Chitosan Graft Copolymers

Abstract: In this study, graft copolymerization of itaconic acid (IA) and crotonic acid (CA) onto the crosslinked chitosan beads were carried out using ammonium persulfate as initiator. Grafted chitosan beads were characterized by FT-IR analysis and grafting percentage determination. Grafting efficiency and add-on percentages values of grafted chitosan beads were determined as 23–29 and 32–47%, respectively. Then, equilibrium isotherms and kinetics of brilliant green adsorption onto grafted chitosan beads were investigated. The results indicated that the pseudo-second-order kinetic model fitted better than the data obtained from pseudo-first-order model for the adsorption of brilliant green onto grafted chitosan beads. The fit of data for brilliant green (BG) adsorption onto grafted chitosan beads suggested that the Langmuir model gave closer fittings than the Freundlich model.

Spectrophotometric determination of trace amounts of iodide-ions in form of ionic associate with brilliant green using electrochemical oxidation

Abstract: A combined method involving electrochemical oxidation of iodide to iodate at a platinum electrode followed by extraction in CCl4 of ionic associates of iodine-iodide complexes with brilliant green, formed in excess of iodide, was developed for the spectrophotometric quantification of iodide. The slope of the calibration curve yields a molar extinction coefficient of ɛ = 3·105 L mol−1cm−1. This method can be used for the quantification of iodide in the concentration range of 3·10−7 − 3·10−6 mol L−1 with a detection limit of 5·10−8 mol L−1. The interfering effect of other ions on the determination of the iodide concentration was also investigated. The method was successfully applied for the determination of iodide in real samples of NaCl and spring water. Relative standard deviation is 1–2%.

Comparative study of Brilliant Green dye adsorption from water by radish peels, Jamun stem and coal.

Abstract: Adsorption is being evolved as an alternative water treatment technique now-a-days for removing dyes, heavy metals and other organic pollutants from water. In the following study, the efficiency of removing Brilliant Green dye from water has been evaluated using two novel and one conventional adsorbent, i.e. Radish (Raphanus sativus var. longipinnatus) peels, Jamun stem (Eugenia jambolana) and coal respectively. The adsorption process is carried out batch wise by using different concentrations of the aqueous dye solution with different adsorbent doses, at a range of initial pH values, agitation rate, varying contact time intervals and temperature. The adsorption capacity of adsorbents is modified by using different chemicals and compared with non-modified adsorbents. The suitability of the adsorbent is tested by fitting the adsorption data on Langmuir and Freundlich isotherms. The results showed that the Jamun stem powder is a more effective adsorbent than Reddish peels for removing dyes from water. It can be used in place of activated coal for removing Brilliant Green dye from waste-water.

Efficient solar energy conversion and storage through photogalvanic cell based on edta: brilliant green and fast green system

Abstract: Quest for devising efficient and cost effective energy systems is on. Solar energy is an everlasting and omnipresent source of clean energy. Photogalvanic cells are a potent medium through which solar light may be harnessed gainfully. A mixed dye system Ethylene diamine tetra acetic acid (EDTA)-brilliant green and fast green has been used in place of a single dye system in the present work. Photopotential, photocurrent and other important operating parameters are recorded for photogalvanic cell based on mixed dye system. Experiments are performed with different concentrations of brilliant green and fast green with EDTA at different pH values to optimize the performance of the cell. Encouraging results have been obtained.

Alkaline hydrolysis of brilliant green in mixed cationic surfactant systems

Abstract: Kinetic measurements were performed for the alkaline hydrolysis of brilliant green — a triphenylmethane dye used as a model compound for probing micellar rate effects. This reaction was studied both in the presence of tetradecyltrimethylammonium bromide (TTAB) and tetradecyltriphenylphosphonium bromide (TTPPBr) and also in binary mixtures of these surfactants at different mole fractions of each. All rate surfactant profiles were analyzed using the pseudo-phase model in order to obtain the regression parameters, including binding constants and rate constants in the micellar pseudo-phase. The reaction was catalyzed by both surfactants. The catalytic factor increases from about 10 for pure TTPPBr to about 38 for pure TTAB. Binding of BG to micellar surface is greater in pure TTAB than in pure TTPPBr but significantly reduced in the surfactant mixtures than in pure components. Reduction of the binding constant becomes more significant as the mole fraction of TTAB is increased in the mixture. The kinetic data have been analyzed in terms of models of Piszkiewicz and Raghavan-Srinivasan which are in good agreement. Open image in new window

Research on adsorption properties of basic brilliant green dye wastewater by bentonite and zeolite

Abstract: In this paper, the sorbent bentonite and zeolite was used to treat the wastewater including basic brilliant green dye were investigated respectively. During this experiment, the quantity of sorbent, the surge time, the concentration of basic brilliant green dye and the pH of the solution, which make different effect on the rate of absorption, have been researched. And the remarkable adsorption conditions of the two sorbents were made certain. The conclusions indicated that when the quantity of bentonite was 25 mg and the surge time was 30 minutes, the absorption rate was over 94%, and when the quantity of zeolite was 180 mg and the surge time was 30 minutes, the absorption rate reached over 92%. So it shows that the adsorption effect of the bentonite is superior to the zeolite, and all they have wide application market.

Photodynamic action of LED-light on standard and clinical strains of Staphylococci, processed by Brilliant Green and Titanium Dioxide

Abstract: We assume that the effectiveness of phototherapy against microorganisms may be increased if together with the photosensitizer a photocatalyst will be used. It was found that the combination of TiO 2 -nanoparticles and Brilliant Green at two-wavelength irradiation with blue (405 nm) and red (625 nm) light provides a strong antimicrobial effect on standard and clinical strains of Staphylococci.

Synthesis and Adsorption Behavior of Magnesium Silicate Gels

Abstract: A novel Magnesium silicate gel(MgO·1.19SiO2) was synthesized by a mild hydrothermal route of Na2SiO3·9H2O and MgCl2·6H2O.The new material(Si-Mg gel) and its calcined product(C-Si-Mg gel) were characterized by BET,SEM,FT-IR and XRD.Effects of calcinations temperature on removal efficiency of basic brilliant green were studied.The results indicate that C-Si-Mg gel which was calcined at 700 ℃ behaved the best adsorbent performance.The equilibrium data were found to be well represented by the Langmuir isotherm equation.The best fit of the kinetic result was achieved by a pseudo second-order equation,with the maximum adsorption capacity up to 476.19mg·g-1.

The controlled potential reduction of crystal violet and brilliant green at the stirred mercury cathode.

Abstract: The application of controlled potential coulometry to the electro-reduction of the triphenylmethane dyestuffs crystal violet and brilliant green is described below. The polarographic work by Kaye and Stonehill (1952) indicated that, like the aminoacridines previously examined (Wilson, Butler, Ingle and Taylor, 1960), these were reduced in two stages each involving the uptake of one electron. The aim of the present work was to seek confirmation of this by direct measurement of the quantities of electricity involved in the reduction of a known amount of dyestuff.

Gamma Radiolysis Studies of Aqueous Solution of Brilliant Green Dye

Abstract: The effect of γ–radiation on colour intensity of aqueous solution of Brilliant Green has been investigated at two different concentrations The degradation of Brilliant Green (BG) has also been investigated in presence of suspended ZnO, by adding different amounts of ZnO Simultaneously the conductance and pH of each solution system were measured before and after γ-irradiation All the γ–irradiations were performed at a dose rate of 060 kGyhr-1 in GC-900 The maximum dose required for the complete degradation of the dye was found to be 039 kGy G(-dye) values were found to decrease with increase in gamma dose and were in the range 426 - 1281 The conductance (76 - 253 μS) and pH values increased marginally with dose for both the concentrations The rate of decolouration was found to be high at lower doses and the efficiency of dye removal was higher at low concentration of the dye This may be attributed to the presence of reaction by-products from the destruction of parent compound build up and compete for reaction intermediate species The rate of reaction and rate constants were calculated and it was found that the degradation reaction follows first order kinetics It was found that the decolouration percentage was more in dye systems in absence of ZnO