Biomedical subjects

Qing-ren Zhu

Publications and source records attributed to Qing-ren Zhu.

3 recordsLinked to original sources

PubMed2005

[Spectral study on intermolecular coupling interaction and relation to microstructure in polyester/inorganic hybrid materials].

The coupling form of the polymeric-inorganic component and the relation between intermolecular special hydrogen bonding interaction and the microstructure of crystallizable polymer, as well as micro-phase separation scale in non-covalently coupled poly (epsilon-caprolactone) (PCL)/silica (SiO2) hybrid materials were investigated by means of Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, wide angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC). The results show that the coupling form between PCL and SiO2 mainly depend on a strong intermolecular hydrogen bonding interaction in the hybrid system. The hydrogen bonding strength increases with increasing TEOS content, while the crystallization of PCL decreases, and the optical transparency of hybrid materials increases. In addition, it affects the scale of micro-phase separation in hybrid materials.

Calorimetry, Differential Scanning↗

PubMed2002

[Simultaneous determination of iron and molybdenum by extraction catalytic spectrophotometry].

In this paper, a new extraction catalytic spectrophotometric method for the simultaneous determination of iron and molybdenum has been studied. The method is based on the difference of the reaction rate of iron(III) and molybdenum(VI) catalyzed oxidation of o-aminophenol by hydrogen peroxide in weak acidic medium at pH 5.5. The reaction time, concentration of o-aminophenol in aqueous phase and degree of reaction are controlled by extraction equilibrium. The absorbance of organic phase is measured at 424 nm. The linear ranges of the method are 0.010-0.30 microgram.mL-1 (for iron) and 0.50-2.0 micrograms.mL-1 (for molybdenum). The method has been applied to the simultaneous determination of iron and molybdenum in soybean with satisfactory results.

Catalysis↗

PubMed2002

[Determination of trace molybdenum by extraction catalytic kinetic spectrophotometry].

A new extraction catalytic kinetic spectrophotometric method for the determination of trace molybdenum is studied. The method is based on the molybdenum (VI) catalytic oxidation of o-aminophenol by hydrogen peroxide in week acidic medium at pH 5.5. The reaction is carried out at room temperature. The reaction time, concentration of o-aminophenol in aqueous phase and degree of reaction are controlled by extraction equilibrium. The absorbance of organic phase is measured at 424 nm. Under the optimum experiment conditions, the linear range of the determination is 0.0050-2.0 mg.L-1, the detection limit is 2.0 x 10(-6) g.L-1. Combining with separation of ionic exchange, the method has been applied to the determination of trace molybdenum in bean samples with satisfactory results. The kinetic equation of extraction catalytic reaction is discussed.

Aminophenols↗