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Jinzhang Gao

Publications and source records attributed to Jinzhang Gao.

9 recordsLinked to original sources
PubMed2006

Determination of 1-naphthylamine by using oscillating chemical reaction.

A simple and rapid analytical method for determining 1-naphthylamine was proposed by perturbation with different amounts of 1-naphthylamine on the classical Belousov-Zhabotinskii (B-Z) oscillating chemical system. The results show that the changes both in oscillating period and amplitude were linearly proportional to the logarithm of the concentration of 1-naphthylamine (logC) very well ranging from 7.08x10(-5) to 7.08x10(-6) molL(-1) and 7.08x10(-5) to 1.0x10(-6) molL(-1), with the corresponding regression coefficient are 0.9957 and 0.9922, respectively. For the later, a lower detection limit of 5.64x10(-9) molL(-1) was obtained. Influence of injection point, temperature and reactant variables on this oscillating system was also investigated in detailed. The results obtained were compared with other determination methods. A possible reaction mechanism was interpreted by using bromide ion selective electrode to inspect the concentration change of Br(-) ion in the oscillating process.

1-Naphthylamine↗
PubMed2006

Degradation of 2,4-dichlorophenol by using glow discharge electrolysis.

Degradation of 2,4-dichlorophenol (2,4-DCP) in aqueous by glow discharge electrolysis (GDE) has been investigated. Ultraviolet (UV) absorption spectra, atomic force microscopy (AFM), high performance liquid chromatography (HPLC) and gas chromatogram-mass spectrum (GC/MS) are used to monitor the degradation process and to identify the major oxidation intermediate products. It has been found that 2,4-DCP undergoes a series of intermediate step, which leads to form a number of intermediate products, mainly isomeric chlorophenols and aliphatic acids. These products are further oxidized, eventually, mineralized into CO(2) and Cl(-). A degradation pathway for 2,4-DCP is proposed on the basis of detection of intermediate compounds.

Chlorophenols↗
PubMed2006

Determination of furfural in an oscillating chemical reaction using an analyte pulse perturbation technique.

A rapid and convenient method for the determination of furfural is presented that is based upon sequential perturbation of the Mn(II)-catalyzed B-Z oscillating system with different amounts of furfural using a continuous-flow stirred tank reactor (CSTR). When the sample was injected, the change in the amplitude and/or period was linearly proportional to the logarithm of the concentration of furfural over the range 3 x 10(-8) approximately 1 x 10(-5) mol L(-1). This method gave a detection limit of 3 x 10(-9) mol L(-1) under optimum conditions. Finally, the possible mechanism of furfural perturbation in the oscillating reaction is discussed. When the furfural was injected into the Mn(II)-catalyzed B-Z oscillating system, the change in the amplitude and/or period was linearly proportional to the logarithm of the concentration of furfural over the range 3 x 10(-8)~1 x 10(-5) mol L(-1), with a detection limit of 3 x 10(-9) mol L(-1) under optimum conditions.

Journal Article↗
PubMed2006

Decoloration of aqueous Brilliant Green by using glow discharge electrolysis.

This paper described a plasma degradation of Brilliant Green (BG) by glow discharge electrolysis. Various influencing factors such as the voltage, the distance between cathode and anode were examined. Ultraviolet (UV) absorption spectra, gas chromatogram-mass spectrum (GC-MS), and chemical oxygen demand (COD) were used to monitor the degradation process and to identify the major oxidation intermediates. It was confirmed that benzoic acid, 1,2,3,4,5,6-cyclohexanehexaol, and carboxylic acids (e.g., oxalic acid, succinic acid and hydroxyacetic acid) were produced in the degradation process. The results showed that BG rapidly underwent degradation and eventually mineralized into CO(2) and H(2)O.

Carbon Dioxide↗
PubMed2003

Determination of caffeine using oscillating chemical reaction in a CSTR.

A new analytical method for the determination of caffeine by the sequential perturbation caused by different amounts of caffeine on the oscillating chemical system involving the manganese(II)-catalyzed reaction between potassium bromate and tyrosine in acidic medium in a CSTR was proposed. The method exposed for the first time in this work. It relies on the relationship between the changes in the oscillation amplitude of the chemical system and the concentration of caffeine. The calibration curve fits a second-order polynomial equation very well when the concentration of caffeine over the range 4.0 x 10(-6) - 1.2 x 10(-4) M (r = 0.9968). The effect of influential variables, such as the concentration of reaction components, injection point, temperature, flow rate and stirring rate were studied. Some aspects of the potential mechanism of action of caffeine on the chemical oscillating system were also discussed. A real sample was determined and the result was satisfactory.

Caffeine↗
PubMed2003

Comparative study on fluorescence enhancement and quenching of europium and terbium chelate anions in cationic micelles.

Fluorescence enhancement and quenching of water soluble chelates of terbium (Tb3+) with Tiron, salicylic acid (SA), 4-sulfonyl salicylic acid (SSA) and acetylacetone (AA) and sparingly soluble chelates of europium (Eu3+) with beta-diketones were comparatively examined in the presence of cetyltrimethyl ammonium bromide (CTMAB) and cetylpyridinium chloride (CPC). By the composition of the complexes, surface tension measurements and spectral analysis, the binding mode of chelate anions to the micellar surface of cationic surfactants was discussed in terms of ion-exchange model. Quenching effect of CPC on the fluorescence of association complexes seems to arise from the charge transfer from a fluorescent ligand to pyridinium cation. In the case of the chelates of Eu3+ with beta-diketones, however, pyridinium ion is only capable of overlapping the aromatic ring of beta-diketones to less extent since the poorly soluble charged chelates have a weak affinity for the highly polar surface of pyridinium cationic micelles. Efficient charge transfer between the excited aromatic beta-diketone and pyridinium cation fails to be established. CPC also shows enhanced effect on fluorescence like CTMAB.

1,2-Dihydroxybenzene-3,5-Disulfonic Acid Disodium ↗
PubMed2003

Plasma degradation of dyes in water with contact glow discharge electrolysis.

Contact glow discharge electrolysis (CGDE) of two dyes, weak acid brilliant red B and weak acid flavine G, was investigated under different concentrations, temperature and mediums. From the variation of their concentration with the reaction time, it was demonstrated that the oxidation would be a first-order reaction. On the base line of UV spectra of solution in the degradation process, we deduced that two dyes underwent the oxidative degradation in CGDE. The rate constants, relevant coefficients and the decolorization degree were displayed under different conditions.

Coloring Agents↗
PubMed2002

Study on the interactions between CuL(2) and Morin with DNA.

Absorption, fluorescence spectral and viscometric studies have been carried out on the interaction of Morin (2',3,4',5,7-pentahydroxyflavone, ) and its Cu complex, CuL(2) x 2H(2)O [L=Morin (2'-OH group deprotonated), ] with calf thymus DNA. CuL(2) shows different spectral characteristics from that of Morin in the presence of DNA. Increasing fluorescence is seen for CuL(2) with DNA addition whereas decreased fluorescence is observed for Morin. Quenching fluorescence is observed for the DNA-EB system when CuL(2) is added whereas slightly quenched fluorescence is seen for the DNA-EB system with Morin addition. The relative viscosity of DNA and the DNA-EB system increases with the addition of CuL(2.) Hypochromism and a smaller shift are observed in the UV-visible spectra of CuL(2) in the presence of DNA and the denatured temperature of DNA is decreased in the presence of CuL(2). The above results suggested that Morin and CuL(2) can both bind to DNA, but the binding mode is different. The complex binds to DNA mainly by intercalation, while Morin binds in a nonintercalating mode.

Animals↗