The adsorptive precipitation between eosin Y (EY) and AgCl colloids at pH 3.73 caused the sensitive color change of the solution. The reaction mechanism between EY and AgCl was analyzed and this reaction was used fo...The adsorptive precipitation between eosin Y (EY) and AgCl colloids at pH 3.73 caused the sensitive color change of the solution. The reaction mechanism between EY and AgCl was analyzed and this reaction was used for determination of Cl^- in trace level by the light-absorption radio variation approach.展开更多
Two novel coordination compounds formulated as [Co2(EY)2(L1)]·2C2H5OH(1) and [Mn2(EY)2(L1)]·2C2H5OH(2)(EY = Eosin Y dianion, L1 = 4,4'-bipyridine) based on Eosin Y dye ligand have been prepare...Two novel coordination compounds formulated as [Co2(EY)2(L1)]·2C2H5OH(1) and [Mn2(EY)2(L1)]·2C2H5OH(2)(EY = Eosin Y dianion, L1 = 4,4'-bipyridine) based on Eosin Y dye ligand have been prepared by solvothermal reactions and structurally characterized. Single-crystal X-ray diffraction studies reveal that compounds 1 and 2 are isostructural. They show weak antiferromagnetic coupling between the adjacent Co^Ⅱ and Mn^Ⅱ ions, respectively.展开更多
Kinetics of homogeneous degradation of Eosin Y (EY), also known as Acid red 87 (CI 45380), are studied, mostly using Fenton’s process, at 30℃ by monitoring its absorbance at 517 nm (λ<sub>max</sub> of E...Kinetics of homogeneous degradation of Eosin Y (EY), also known as Acid red 87 (CI 45380), are studied, mostly using Fenton’s process, at 30℃ by monitoring its absorbance at 517 nm (λ<sub>max</sub> of EY). This process is one of the advanced oxidation processes (AOPs). Mixture of H<sub>2</sub>O<sub>2</sub> and Fe(II) ion in acetate buffer medium (pH 2.74 - 4.56) generates hydroxyl free radicals (?OH) which attack the dye molecules, resulting in degradation of the dye molecules. Results show that the initial rate of EY degradation decreases with the increasing of solution pH because of removal of kinetically important Fe (iron) species through formation of ferric hydroxide. On the other hand, the rate increases with increasing the concentrations of H<sub>2</sub>O<sub>2</sub>, Fe(II) and EY at low solution pH. The initial rate increases with increasing of concentration of H2O2 and, subsequently remains unaffected with further increase of its concentration at a constant Fe(II) concentration because of the enhanced scavenging environment created by H<sub>2</sub>O<sub>2</sub> at its higher concentration. The initial rate also increases with increasing of concentration of Fe(II) at a constant H<sub>2</sub>O<sub>2</sub> concentration and remains unaffected with its further increase. EY concentration also enhances the initial rate at low pH. However, the initial rate is significantly enhanced by UV light. This is because of formation of additional hydroxyl radicals through excitation of the dye molecules by UV light. During the period of experiment, EY in aqueous solution alone hardly suffered any degradation. Degradation mechanism of EY by the Fenton and photo-Fenton’s processes is also discussed. Statistical analysis was used to validate the experimental results. Low values of the standard deviation for both the initial rate and % degradation indicated the consistency of the experimental data.展开更多
The adsorption behavior of eosin yellow (EY) from aqueous solution onto γ-Al<sub>2</sub>O<sub>3</sub> nanoparticles in batch technique was studied. γ-Al<sub>2</sub>O<sub>3&l...The adsorption behavior of eosin yellow (EY) from aqueous solution onto γ-Al<sub>2</sub>O<sub>3</sub> nanoparticles in batch technique was studied. γ-Al<sub>2</sub>O<sub>3</sub> NPs was prepared and characterized by SEM, TEM, XRD and FTIR analysis. The effect of pH, dosage of adsorbent, contact time, temperature, and the initial concentration of dye was investigated. The maximum amount of dye removal found about 99.36% at pH4, the adsorption dose 1g/L, with the initial dye concentration of 100 mg/L, and the temperature of 25°C, with contact time 120 min. The adsorption behavior of the eosin yellow dye is applicable to Langmuir isotherm model, with the maximum sorption capacity of 47.78 mg/g of γ-Al<sub>2</sub>O<sub>3</sub>. The kinetic data also described by the pseudo-second-order model with a correlation coefficient (0.9999), and the mechanism of the process showed a multi-linear steps and the intra-particle diffusion was not only rate controlling step. The adsorption process was endothermic with positive enthalpy of 121.8 kJ/mol, and showed spontaneous process with a mean free energy -5.19 kJ/mol, and increase randomness, 369.77 J/mol. k, at the adsorbent solution interface. The adsorption process was chemisorption in nature The activation energy estimated from Arrhenius and modified Arrhenius is 40.9 kJ/mol, 106.37 kJ/mol respectively. The sticking probability of EY onto Al<sub>2</sub>O<sub>3</sub> NPs very high estimated from the value of S* < 1, (4.82E-19).展开更多
A novel chemiluminescence (CL) system was established for the determination of puerarin in pharmaceutical preparations. It was shown that a strong CL signal was observed when Eosin Y reacted with the hydroxyl radica...A novel chemiluminescence (CL) system was established for the determination of puerarin in pharmaceutical preparations. It was shown that a strong CL signal was observed when Eosin Y reacted with the hydroxyl radicals which were generated from Fenton reagent in acidic medium. The CL intensity was decreased significantly when puerarin was added to the reaction system and partially scavenged the hydroxyl radicals in the solution. The extent of decrease in the CL intensity had a good stoichiometrical relationship with puerarin concentration. Based on this, a new method for the determination of puerarin using a flow injection chemiluminescence technique was developed. The experimental parameters that affected the CL intensity were optimized. Under the optimal conditions, the linear range for puerarin concentration was 8.0 × 10^-8--2.0 × 10^-6 mol/L (R = 0.9982) with a detection limit of 7.5 × 10^-9 mol/L (S/N= 3) and the relative standard deviation was method was applied to the determination of puerarin in a 1.7% for 4.0× 10^-7 mol/L puerarin (n= 11). The proposed puerarin injection with satisfactory results.展开更多
Sonogashira cross-coupling reaction is significant for the formation of C―C bonds and the creation of new substance in organic synthesis,which is usually catalyzed using noble metal,such as palladium or non-precious ...Sonogashira cross-coupling reaction is significant for the formation of C―C bonds and the creation of new substance in organic synthesis,which is usually catalyzed using noble metal,such as palladium or non-precious metal,such as copper under harsh reaction conditions.Herein,we report the encapsulation of an organic dye(i.e.,Eosin Y,EY)into a Cu(I)cyclic trinuclear unit(CTU)based covalent-metal organic framework(CMOF),namely EY@JNM-1,which demonstrates outstanding photocatalytic performance for the Sonogashira cross-coupling reaction of iodobenzene with alkynes.The EY@JNM-1 not only exhibited high catalytic activity for the alkynes(>99%conversion)and excellent selectivity for the cross-coupling product(>99%)under mild conditions,but also displayed excellent stability and recyclability.展开更多
Chemical fixing of xanthene dye (eosin Y) on the surface of TiO2 electrode was carried out by modifying the electrode with silane-coupling reagent to obtain stable dye-sensitized TiO2 electrode. Such silane modificati...Chemical fixing of xanthene dye (eosin Y) on the surface of TiO2 electrode was carried out by modifying the electrode with silane-coupling reagent to obtain stable dye-sensitized TiO2 electrode. Such silane modification can not only evidently enhance the stability of dye-sensitized TiO2 electrode but also im-prove the energy conversion efficiency of the assembled cells by increasing short-circuit photocurrent (JSC) and open-circuit photovoltage (VOC). It was found that the improvements of cell performances differ depending on the composition of the electrolyte. The optimum cell of the cell performance was achieved in the electrolyte with 0.5 mol/L TBAI/0.05 mol/L I2/EC:PC(3:1 w/w), yielding JSC of 4.69 mA·cm?2, VOC of 0.595 V, fill factor (FF) of 0.64 and η of 1.78%. Different spectroscopic techniques including UV-Vis spectra, fluorescence spectra, EIS and dark current measurements were employed to derive reasonable analysis and explanations.展开更多
Thin hybrid films of ZnO/eosin-Y were prepared by electrodeposition at-0.8 and-0.9 V in aqueous and non-aqueous baths at temperatures ranging from 40 to 90 ℃ with dye concentrations of 100 and 400 μmol·L-1.The ...Thin hybrid films of ZnO/eosin-Y were prepared by electrodeposition at-0.8 and-0.9 V in aqueous and non-aqueous baths at temperatures ranging from 40 to 90 ℃ with dye concentrations of 100 and 400 μmol·L-1.The films were characterized by X-ray diffraction (XRD),scanning electron microscopy (SEM),energy-dispersive X-ray analysis (EDX),and absorption spectroscopy.The films prepared in a non-aqueous bath were non-porous and did not adsorb dye molecules on their surface.However,the films grown in aqueous media were porous in nature and adsorbed dye during the deposition of ZnO.Preferential growth of the film along the (002) face was observed,and the highest crystallinity was achieved when the film was deposited at 60 ℃.The maximum absorption was achieved for the films grown at 60 to 70 ℃,a deposition potential of-0.9 V,and a dye concentration of 100 μmol·L-1.展开更多
In a weak acidic medium(pH 2.4-2.8),eosin Y molecules(H2L) could replace water molecules to associate with Triton X-100 to form hydrophobic hydrogen bonding complexes.These complexes could further aggregate to form na...In a weak acidic medium(pH 2.4-2.8),eosin Y molecules(H2L) could replace water molecules to associate with Triton X-100 to form hydrophobic hydrogen bonding complexes.These complexes could further aggregate to form nanoparticles through the squeezing action of the water phase and Van Der Waals force,resulting in changes in the absorption spectrum and fluorescence quenching of EY as well as the significant enhancement of resonance Rayleigh scattering.This enables the sensitive determination of Triton X-100 using the fading spectrophotometry,fluorescence quenching method and RRS method.Among them,the RRS method shows the highest sensitivity with a detection limit of 20.6 ng mL-1 for Triton X-100.The optimum experimental conditions and factors that affect the absorption,fluorescence and RRS spectra were tested.The effects of coexisting substances were investigated and the results showed good selectivity.Based on these results,new spectrophotometric methods,fluorescence quenching method and RRS method for the determination of Triton X-100,were established.The hydrogen bonding association of eosin Y with Triton X-100 and the formation of nanoparticles as well as their effects on related spectral characteristics were discussed utilizing infrared,transmission electron microscope technique and quantum chemical method.展开更多
基金National Natural Science Foundation of China(No.20477030).
文摘The adsorptive precipitation between eosin Y (EY) and AgCl colloids at pH 3.73 caused the sensitive color change of the solution. The reaction mechanism between EY and AgCl was analyzed and this reaction was used for determination of Cl^- in trace level by the light-absorption radio variation approach.
基金supported by the National Natural Science Foundation of China(21503230 and 21571175)State Key Laboratory of Structural Chemistry,Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences
文摘Two novel coordination compounds formulated as [Co2(EY)2(L1)]·2C2H5OH(1) and [Mn2(EY)2(L1)]·2C2H5OH(2)(EY = Eosin Y dianion, L1 = 4,4'-bipyridine) based on Eosin Y dye ligand have been prepared by solvothermal reactions and structurally characterized. Single-crystal X-ray diffraction studies reveal that compounds 1 and 2 are isostructural. They show weak antiferromagnetic coupling between the adjacent Co^Ⅱ and Mn^Ⅱ ions, respectively.
文摘Kinetics of homogeneous degradation of Eosin Y (EY), also known as Acid red 87 (CI 45380), are studied, mostly using Fenton’s process, at 30℃ by monitoring its absorbance at 517 nm (λ<sub>max</sub> of EY). This process is one of the advanced oxidation processes (AOPs). Mixture of H<sub>2</sub>O<sub>2</sub> and Fe(II) ion in acetate buffer medium (pH 2.74 - 4.56) generates hydroxyl free radicals (?OH) which attack the dye molecules, resulting in degradation of the dye molecules. Results show that the initial rate of EY degradation decreases with the increasing of solution pH because of removal of kinetically important Fe (iron) species through formation of ferric hydroxide. On the other hand, the rate increases with increasing the concentrations of H<sub>2</sub>O<sub>2</sub>, Fe(II) and EY at low solution pH. The initial rate increases with increasing of concentration of H2O2 and, subsequently remains unaffected with further increase of its concentration at a constant Fe(II) concentration because of the enhanced scavenging environment created by H<sub>2</sub>O<sub>2</sub> at its higher concentration. The initial rate also increases with increasing of concentration of Fe(II) at a constant H<sub>2</sub>O<sub>2</sub> concentration and remains unaffected with its further increase. EY concentration also enhances the initial rate at low pH. However, the initial rate is significantly enhanced by UV light. This is because of formation of additional hydroxyl radicals through excitation of the dye molecules by UV light. During the period of experiment, EY in aqueous solution alone hardly suffered any degradation. Degradation mechanism of EY by the Fenton and photo-Fenton’s processes is also discussed. Statistical analysis was used to validate the experimental results. Low values of the standard deviation for both the initial rate and % degradation indicated the consistency of the experimental data.
文摘The adsorption behavior of eosin yellow (EY) from aqueous solution onto γ-Al<sub>2</sub>O<sub>3</sub> nanoparticles in batch technique was studied. γ-Al<sub>2</sub>O<sub>3</sub> NPs was prepared and characterized by SEM, TEM, XRD and FTIR analysis. The effect of pH, dosage of adsorbent, contact time, temperature, and the initial concentration of dye was investigated. The maximum amount of dye removal found about 99.36% at pH4, the adsorption dose 1g/L, with the initial dye concentration of 100 mg/L, and the temperature of 25°C, with contact time 120 min. The adsorption behavior of the eosin yellow dye is applicable to Langmuir isotherm model, with the maximum sorption capacity of 47.78 mg/g of γ-Al<sub>2</sub>O<sub>3</sub>. The kinetic data also described by the pseudo-second-order model with a correlation coefficient (0.9999), and the mechanism of the process showed a multi-linear steps and the intra-particle diffusion was not only rate controlling step. The adsorption process was endothermic with positive enthalpy of 121.8 kJ/mol, and showed spontaneous process with a mean free energy -5.19 kJ/mol, and increase randomness, 369.77 J/mol. k, at the adsorbent solution interface. The adsorption process was chemisorption in nature The activation energy estimated from Arrhenius and modified Arrhenius is 40.9 kJ/mol, 106.37 kJ/mol respectively. The sticking probability of EY onto Al<sub>2</sub>O<sub>3</sub> NPs very high estimated from the value of S* < 1, (4.82E-19).
基金Supported by the Key Program Projects of National Natural Science Foundation of China (20431030)the National Natural Sci-ence Foundation of China (20671032,20676027)the Key Program Projects of Heilongjiang Province Natural Science Foundation of China (ZJG0602 -01)
基金Project supported by Guangxi Science Foundation of China (No. 2010GXNSFA013001).
文摘A novel chemiluminescence (CL) system was established for the determination of puerarin in pharmaceutical preparations. It was shown that a strong CL signal was observed when Eosin Y reacted with the hydroxyl radicals which were generated from Fenton reagent in acidic medium. The CL intensity was decreased significantly when puerarin was added to the reaction system and partially scavenged the hydroxyl radicals in the solution. The extent of decrease in the CL intensity had a good stoichiometrical relationship with puerarin concentration. Based on this, a new method for the determination of puerarin using a flow injection chemiluminescence technique was developed. The experimental parameters that affected the CL intensity were optimized. Under the optimal conditions, the linear range for puerarin concentration was 8.0 × 10^-8--2.0 × 10^-6 mol/L (R = 0.9982) with a detection limit of 7.5 × 10^-9 mol/L (S/N= 3) and the relative standard deviation was method was applied to the determination of puerarin in a 1.7% for 4.0× 10^-7 mol/L puerarin (n= 11). The proposed puerarin injection with satisfactory results.
基金supported by the National Natural Science Foundation of China(Nos.21731002,21975104,21901085)the Guangdong Major Project of Basic and Applied Research,China(No.2019B030302009)+2 种基金the Guangdong Basic and Applied Basic Research Foundation,China(No.2019B151502024)the Guangdong Province Pearl River Scholar Funded Scheme,China(No.2019)the Fundamental Research Funds for the Central Universities,China(No.21619315).
文摘Sonogashira cross-coupling reaction is significant for the formation of C―C bonds and the creation of new substance in organic synthesis,which is usually catalyzed using noble metal,such as palladium or non-precious metal,such as copper under harsh reaction conditions.Herein,we report the encapsulation of an organic dye(i.e.,Eosin Y,EY)into a Cu(I)cyclic trinuclear unit(CTU)based covalent-metal organic framework(CMOF),namely EY@JNM-1,which demonstrates outstanding photocatalytic performance for the Sonogashira cross-coupling reaction of iodobenzene with alkynes.The EY@JNM-1 not only exhibited high catalytic activity for the alkynes(>99%conversion)and excellent selectivity for the cross-coupling product(>99%)under mild conditions,but also displayed excellent stability and recyclability.
基金Supported by the National Research Fund for Fundamental Key Project (Grant No. 2006CB202605)High-Tech Research and Development Program of China (Grant No. 2007AA05Z439)National Natural Science Foundation of China (Grant No. 20873162)
文摘Chemical fixing of xanthene dye (eosin Y) on the surface of TiO2 electrode was carried out by modifying the electrode with silane-coupling reagent to obtain stable dye-sensitized TiO2 electrode. Such silane modification can not only evidently enhance the stability of dye-sensitized TiO2 electrode but also im-prove the energy conversion efficiency of the assembled cells by increasing short-circuit photocurrent (JSC) and open-circuit photovoltage (VOC). It was found that the improvements of cell performances differ depending on the composition of the electrolyte. The optimum cell of the cell performance was achieved in the electrolyte with 0.5 mol/L TBAI/0.05 mol/L I2/EC:PC(3:1 w/w), yielding JSC of 4.69 mA·cm?2, VOC of 0.595 V, fill factor (FF) of 0.64 and η of 1.78%. Different spectroscopic techniques including UV-Vis spectra, fluorescence spectra, EIS and dark current measurements were employed to derive reasonable analysis and explanations.
基金supported by the Spanish Government through MCINN Grant (MAT2009-14625-C03-03)MEC Financial Fund (SAB2010-0019) for Singh, K. C.
文摘Thin hybrid films of ZnO/eosin-Y were prepared by electrodeposition at-0.8 and-0.9 V in aqueous and non-aqueous baths at temperatures ranging from 40 to 90 ℃ with dye concentrations of 100 and 400 μmol·L-1.The films were characterized by X-ray diffraction (XRD),scanning electron microscopy (SEM),energy-dispersive X-ray analysis (EDX),and absorption spectroscopy.The films prepared in a non-aqueous bath were non-porous and did not adsorb dye molecules on their surface.However,the films grown in aqueous media were porous in nature and adsorbed dye during the deposition of ZnO.Preferential growth of the film along the (002) face was observed,and the highest crystallinity was achieved when the film was deposited at 60 ℃.The maximum absorption was achieved for the films grown at 60 to 70 ℃,a deposition potential of-0.9 V,and a dye concentration of 100 μmol·L-1.
基金support from the National Natural Science Foundation of China (20875078)the Youth Fund of Southwest University (20710403)
文摘In a weak acidic medium(pH 2.4-2.8),eosin Y molecules(H2L) could replace water molecules to associate with Triton X-100 to form hydrophobic hydrogen bonding complexes.These complexes could further aggregate to form nanoparticles through the squeezing action of the water phase and Van Der Waals force,resulting in changes in the absorption spectrum and fluorescence quenching of EY as well as the significant enhancement of resonance Rayleigh scattering.This enables the sensitive determination of Triton X-100 using the fading spectrophotometry,fluorescence quenching method and RRS method.Among them,the RRS method shows the highest sensitivity with a detection limit of 20.6 ng mL-1 for Triton X-100.The optimum experimental conditions and factors that affect the absorption,fluorescence and RRS spectra were tested.The effects of coexisting substances were investigated and the results showed good selectivity.Based on these results,new spectrophotometric methods,fluorescence quenching method and RRS method for the determination of Triton X-100,were established.The hydrogen bonding association of eosin Y with Triton X-100 and the formation of nanoparticles as well as their effects on related spectral characteristics were discussed utilizing infrared,transmission electron microscope technique and quantum chemical method.