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Sun D.-L.,Central South University of forestry and Technology | Yu X.C.,Yueyang Vocational and Technical College | Wang R.,Central South University of forestry and Technology
Asian Journal of Chemistry | Year: 2013

A woodceramics is prepared from liquefied corncob and poplar powder. The basic property of this material is closely correlated to the carbonization temperature and liquefied corncob content. The thermogravimetric analysis indicates that the high liquefied corncob content can decrease weight loss. X-ray diffraction analysis shows that higher carbonization temperature can improve the graphitization degree of this material, but the phase composition is not mainly related to the liquified corncob content. Scanning electron microscopy confirms that the poplar powder is as a natural plant template and the pore of woodceramics partly keeps the native characteristics of the wood with size ranging from 5 to 20 μm. It is porous carbon material with three-dimensional network structure.

Yu X.-C.,Yueyang Vocational and Technical College | Sun D.-L.,Central South University of forestry and Technology
Asian Journal of Chemistry | Year: 2013

Pollution of inorganic acid can be reduced, pectin yield and purity can be increased by using microwave to process orange peels and then adding complex enzyme to extract pectin. The infrared spectrum showed that orange pectin contained a relatively huge amount of carbohydrates, but no protein. The extract technology was optimized by orthogonal experiments at 250 W microwave power, 50 °C microwave heating temperature, 10 min microwave processing time, 1 h single extraction time, buffer pH 4.5, 50 °C enzyme extraction temperature and 0.9 % enzymatic dosage. Enzyme extraction was performed three times. The average yield in orange peel pectin was 22.12 %, which was much higher than the pectin extraction yield using conventional water bath method under the same conditions.

Delin S.,Central South University of forestry and Technology | Xianchun Y.,Yueyang Vocational and Technical College | Debin S.,Central South University of forestry and Technology | Rong W.,Central South University of forestry and Technology
Applied Mechanics and Materials | Year: 2012

A woodceramics makes from liquefaction wood and wood powder, the basic property connects with sintering temperature and liquefaction wood content. Thermo gravimetric analysis indicates that higher liquefaction wood content lead to reduce the weight loss. Scanning electron microscopy observation shows that wood powder is as a natural plant template and the basic structure of wood can partly keep. The apparent density increases before about 1100°C, and then decreases as temperature gets further; but the apparent porosity increases continuous; bending strength increases from 8.45 MPa to 11.87 MPa when the liquefaction wood content raises 60%-120%. Meanwhile, elevation of liquefaction wood content and sintering temperature can reduce abrasion loss. © (2012) Trans Tech Publications, Switzerland.

Yu X.,Yueyang Vocational and Technical College | Sun D.,Central South University of forestry and Technology | Li X.,University of South China
Journal of Wood Science | Year: 2011

To improve its overall performance, fast-growing poplar was modified using the vacuum-pressure-vacuum impregnation method with a urea-formaldehyde resin-sodium montmorillonite intercalation as the modification solution. The results showed that considerable amounts of urea-formaldehyde resin and montmorillonites entered the poplar tracheid, and some entered the microporous wood. These substances formed bonds with the active groups in timber, causing reduced crystallinity in the amorphous region of the poplar, a decreased level of free hydroxyl, and an enhanced association with hydroxyl and ether bonds. The density, dimensional stability, and mechanical properties of poplar were markedly improved. The best results were obtained with 14% sodium montmorillonite and 20% ureaformaldehyde resin: the bending resistance, compressive resistance, and elastic modulus increased by 19. 37%, 30. 24%, and 50. 06%, respectively. With elevated levels of sodium montmorillonite, the impact toughness and wear rate decreased. © 2011 The Japan Wood Research Society.

Fang Z.-H.,Yueyang Vocational and Technical College | Fang Z.-H.,Hunan University | Lu L.-M.,Hunan University | Zhang X.-B.,Hunan University | And 4 more authors.
Electroanalysis | Year: 2011

A new third-generation biosensor for H2O2 assay was developed on the basis of the immobilization of horseradish peroxidase (HRP) in a nanocomposite film of carbon nanotubes (CNTs)-SBA-15 modified gold electrode. The biological activity of HRP immobilizing in the composite film was characterized by UV-vis spectra. The HRP immobilized in the nanocomposite matrix displayed excellent electrocatalytic activity to the reduction of H2O2. The effects of the experimental variables such as solution pH and working potential were investigated using steady-state amperometry. Under the optimal conditions, the resulting biosensor showed a linear range from 1μM to 7mM and a detection limit of 0.5μM (S/N=3). Moreover, the stability and reproducibility of this biosensor were evaluated with satisfactory results. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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