The plane-wave pseudopotential function method, based on density-functional theory, has been used to calculate the adsorption, electronic band structures, orbitals and optical absorption spectrum of [Fe(CN)6]^4- on ...The plane-wave pseudopotential function method, based on density-functional theory, has been used to calculate the adsorption, electronic band structures, orbitals and optical absorption spectrum of [Fe(CN)6]^4- on TiOz anatase(101) surface. Our calculations reveal that the surface-modified anatase system has large adsorption energy and a much narrower band gap. [Fe(CN)6]^4- adsorption on the (101) surface could lead to a large red shift of the anatase optical absorption threshold, which extends into a visible region significantly. The calculated results are in agreement with the experiment and other theoretical studies reasonably. It is very important for the understanding and further development ofphotovoltaic materials that are active under visible light.展开更多
A rapid and sensitive flow-injection chemiluminescence(CL) method for the determination of glipizide was developed on the basis of finding that glipizide can enhance the CL intensity of the luminol-K3Fe(CN)6 syste...A rapid and sensitive flow-injection chemiluminescence(CL) method for the determination of glipizide was developed on the basis of finding that glipizide can enhance the CL intensity of the luminol-K3Fe(CN)6 system.In optimum condition,the increased CL intensity was directly proportional to the concentration of glipizide in the range from 4.0×108 g/mL to 1.0×106 g/mL and the detection limit was 1.0×108 g/mL glipizide.The relative standard deviation(RSD) of the developed method was 2.1% with 11 repeated measurements of 1.0×107 g/mL glipizide.The developed method has been successfully applied to the analysis of glipizide in its pharmaceutical preparations.展开更多
Cyclic voltammetry and in situ microscopic FTIR spectroelectrochemistry were used for the electrochemical and vibrational characterizations of the reduction process of K 3Fe(CN) 6 in polyethylene glycol(PEG) wi...Cyclic voltammetry and in situ microscopic FTIR spectroelectrochemistry were used for the electrochemical and vibrational characterizations of the reduction process of K 3Fe(CN) 6 in polyethylene glycol(PEG) with LiClO 4 as supporting electrolyte at a Pt microelectrode. The rate of electron transfer is a function of the concentration of the supporting electrolyte. The redox potentials and cyclic voltammetric currents vary with Li/O molar ratio. The in situ spectroelectrochemistry shows that the infrared spectra are influenced by the concentration of LiClO 4. The bridging cyanide groups with a structure Fe Ⅱ—C≡N…Fe Ⅱ—C≡N are formed during the reduction process of K 3Fe(CN) 6. There may be an activated complex between the Li + cation and the complex anion.展开更多
A water-in-oil (W/O) microemulsion composed of Triton X-100, n-hexanol, n-hexane and water solution with hydrochloric acid was prepared. K3Fe(CN)6 was added in as a water-soluble electroactive probe, and its electroch...A water-in-oil (W/O) microemulsion composed of Triton X-100, n-hexanol, n-hexane and water solution with hydrochloric acid was prepared. K3Fe(CN)6 was added in as a water-soluble electroactive probe, and its electrochemical behavior was investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). It is found that the H+ concentration of the water phase has a great effect on the conductivity of the W/O microemulsion, and hence influences the electrochemical behavior of K3Fe(CN)6. When the pH value of water phase is about 7, the electrical conductivity of the W/O microemulsion is only 1.2×10-6 S/cm, and K3Fe(CN)6 almost cannot react at the glassy carbon electrode. But when the H+ concentration is more than 3 mol/L, the W/O microemulsion has a good electrical conductivity and K3Fe(CN)6 shows good electrochemical performance in it. The results of CV and EIS studies indicate that the electrochemical behavior of Fe(CN)63-/Fe(CN)64- in the W/O microemulsion is different from that in the aqueous solution. This may be due to the unique liquid structure of the W/O microemulsion and the unique mass transfer in the W/O microemulsion.展开更多
基金the Scientific and Technology Foundation of Fuzhou University and the Key Project of Fujian Province (2005HZ01-2-6)
文摘The plane-wave pseudopotential function method, based on density-functional theory, has been used to calculate the adsorption, electronic band structures, orbitals and optical absorption spectrum of [Fe(CN)6]^4- on TiOz anatase(101) surface. Our calculations reveal that the surface-modified anatase system has large adsorption energy and a much narrower band gap. [Fe(CN)6]^4- adsorption on the (101) surface could lead to a large red shift of the anatase optical absorption threshold, which extends into a visible region significantly. The calculated results are in agreement with the experiment and other theoretical studies reasonably. It is very important for the understanding and further development ofphotovoltaic materials that are active under visible light.
基金financial support from Institute of Analytical Sciences,Xi'an
文摘A rapid and sensitive flow-injection chemiluminescence(CL) method for the determination of glipizide was developed on the basis of finding that glipizide can enhance the CL intensity of the luminol-K3Fe(CN)6 system.In optimum condition,the increased CL intensity was directly proportional to the concentration of glipizide in the range from 4.0×108 g/mL to 1.0×106 g/mL and the detection limit was 1.0×108 g/mL glipizide.The relative standard deviation(RSD) of the developed method was 2.1% with 11 repeated measurements of 1.0×107 g/mL glipizide.The developed method has been successfully applied to the analysis of glipizide in its pharmaceutical preparations.
文摘Cyclic voltammetry and in situ microscopic FTIR spectroelectrochemistry were used for the electrochemical and vibrational characterizations of the reduction process of K 3Fe(CN) 6 in polyethylene glycol(PEG) with LiClO 4 as supporting electrolyte at a Pt microelectrode. The rate of electron transfer is a function of the concentration of the supporting electrolyte. The redox potentials and cyclic voltammetric currents vary with Li/O molar ratio. The in situ spectroelectrochemistry shows that the infrared spectra are influenced by the concentration of LiClO 4. The bridging cyanide groups with a structure Fe Ⅱ—C≡N…Fe Ⅱ—C≡N are formed during the reduction process of K 3Fe(CN) 6. There may be an activated complex between the Li + cation and the complex anion.
基金Projects(20673036, J0830415) supported by the National Natural Science Foundation of ChinaProjects(05JT1026, 2007JT2013) supported by the Science Technology Project of Hunan Province, China
文摘A water-in-oil (W/O) microemulsion composed of Triton X-100, n-hexanol, n-hexane and water solution with hydrochloric acid was prepared. K3Fe(CN)6 was added in as a water-soluble electroactive probe, and its electrochemical behavior was investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). It is found that the H+ concentration of the water phase has a great effect on the conductivity of the W/O microemulsion, and hence influences the electrochemical behavior of K3Fe(CN)6. When the pH value of water phase is about 7, the electrical conductivity of the W/O microemulsion is only 1.2×10-6 S/cm, and K3Fe(CN)6 almost cannot react at the glassy carbon electrode. But when the H+ concentration is more than 3 mol/L, the W/O microemulsion has a good electrical conductivity and K3Fe(CN)6 shows good electrochemical performance in it. The results of CV and EIS studies indicate that the electrochemical behavior of Fe(CN)63-/Fe(CN)64- in the W/O microemulsion is different from that in the aqueous solution. This may be due to the unique liquid structure of the W/O microemulsion and the unique mass transfer in the W/O microemulsion.