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Zhi-Hao Jin

Publications and source records attributed to Zhi-Hao Jin.

4 recordsLinked to original sources
PubMed2005

[Raman spectrum of nano-graphite synthesized by explosive detonation].

The nano-graphite powder synthesized by the detonation of explosives with negative oxygen balance is a new powder material with potential applications. In this work, the preparation of nano-graphite powder in steel chamber by pure TNT (trinitrotoluene) explosives has been introduced. In the synthesis process, the protective gases in the steel chamber are N2, CO2 and Ar, and the pressure is 0.25-2 atm. Raman spectrum of the nano-graphite was measured. The characteristic Raman band assigned to sp2 of graphite has been observed at about 1 585 cm(-1) with half-peak width of 22 cm(-1). The peak shifted to a higher frequency by 5 cm(-1) compared with that of bulk graphite. The authors explain this blue shift phenomenon by size effect. The average size of nanographite from Raman measurement is 2.97-3.97 nm. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to measure the structure and particle size of the nano-graphite. The crystallite size of nano-graphite estimated from XRD andTEM are 2.58 nm (acid untreated) and 1.86 nm (acid treated) respectively, which is in accord with the results of the measurement approximately.

Argon↗
PubMed2005

[Studies on nano-diamond prepared by explosive detonation by Raman and infrared spectroscopy].

Nano-diamond was synthesized by TNT/RDX explosives detonation in a steel chamber and characterized by X-ray diffraction (XRD), laser Raman spectroscopy, and infrared spectroscopy. XRD results indicate that nano-diamond has cubic diamond structure. The parameter of unit cell of nano-diamond is 0.359 23 nm and is 0.72% larger than that of the bulk diamond. The high-density defects and other impurity atoms in the nano-diamond structure may lead to the large lattice constant. The examination results of Raman spectra show that the Raman band is broader and shifts to l ow frequency by 3 cm(-1), because the size of nano-diamond reaches nanometer order. There is little graphite in the nano-diamond. There are two peaks in FTIR of the nano-diamond, which are characteristic peaks of diamond at 1 262 and 1 134 cm(-1). Besides these two peaks, there are six peaks at 3 422, 1 643, 2 971, 2 930, 2 857 and 1 788 cm(-1) respectively. The FTIR bands at 2 930 and 2 857 cm(-1) are the antisymmetrical and symmetrical stretch vibration absorption spectra of CH2 respectively. The 3 422 cm(-1) is the stretch vibration absorption peak of O-H. The 1 634 cm(-1) confirms that there are H2O in the nano-diamond. The 2 971 cm(-1) is the antisymmetrical stretch vibration absorption peak of CH3. The 1 788 cm(-1) is the stretch vibration absorption peak of C=O. These indicate that there are H and O elements in the nano-diamond. From the mechanism of the nano-diamond, the authors discuss the reason for the vibration absorption peaks of O-H, CH2, CH3, and C=O, existing in the FTIR of the nano-diamond.

Algorithms↗
PubMed2004

Polyelectrolyte-stabilized glucose biosensor based on woodceramics as electrode.

OBJECTIVE: Different biosensors for early diagnosis of diabetes have been discussed increasingly. We demonstrate the applicability of a glucose biosensor for rapid and quantitative determination of glucose in experimental sample solutions. DESIGN AND METHODS: Polyethylenimine (PEI)-stabilized glucose oxidase (GOD) was used for the construction of stable glucose biosensor utilizing a simple manufacture procedure. The stabilized glucose oxidase was immobilized by physical adsorption into activated porous and conductive carbonaceous material-woodceramics that served as the immobilization matrix and the electrochemical transducer. The optimum parameters for the construction of the biosensor and the influences of pH and temperature on the biosensor response were explored. RESULTS: Optimum results were obtained using soaking solutions of 2300 U/ml GOD, 10 mg/ml mediator toluidine blue O (TBO), and 2.0%, w/v PEI. The sensitivity of the resulting biosensor for glucose was 1.22 microA/mM, with a linear response in the concentration range of 0.5-7 mM. The sensor-to-sensor reproducibility was good, the relative standard deviation (R.S.D.) being less than 8.0%. The storage and operational stabilities of the glucose biosensor were good. CONCLUSIONS: The glucose biosensor provides reproducible and quantitative information on glucose within minutes and is applicable for the detection of glucose in experimental samples.

Aspergillus niger↗