Shen F.,Zhejiang University |
Li F.,Zhejiang University |
Liu D.,Zhejiang University |
Xu H.,Zhejiang University |
And 2 more authors.
Wine ageing status identification is of great commercial and scientific interest, as wine quality and value are closely related to the organoleptic characteristics developed during the ageing process. In this study, Chinese rice wines from three well-known wineries (" Guyuelongshan", "Kuaijishan" and "Pagoda") were analyzed for 21 chemical parameters, including six conventional parameters, five sugars, lactic acid and nine macro-elements. Then the experimental data were subjected to multivariate statistical analysis to predict and classify samples of different ageing status (3, 9, 15, 21, and 33 months). Systematic differences between samples were revealed by a two-way analysis of variance (ANOVA) and principal component analysis (PCA). Discrimination model built by forward stepwise linear discriminant analysis (LDA) based on the 16 selected parameters achieved 88.5% accuracy in leave-one-out (LOO) cross-validation. The most five discriminant variables were Zn, Mn, alcohol, Cu and Al, respectively. When the discrimination was performed on the samples from each winery, the classification accuracy in LOO cross-validation was 97.7%, 91.1% and 78.0%, respectively. The results demonstrated that these chemical parameters have the potential to enable the authentication of ageing status of rice wine. © 2011 Elsevier Ltd. Source
Xu J.,Lanzhou University of Technology |
Chen J.,Shaoxing Testing Institute of Quality Technical Supervision |
Yang S.,Lanzhou University of Technology |
Zhang L.,Lanzhou University of Technology |
Lu J.,China National Erzhong Group Co.
International Journal of Nanoparticles
Copper nanoparticles are prepared by electrochemical method with various current density in emulsion containing sodium dodecyl sulfate, tween80, dodecyl mercaptan, CuSO4·5H2O. The resulting copper nanoparticles are investigated by XRD, TEM and FT-IR. The result shows that great changes have taken place in the size, the dispersibility, and the distribution of particles size as the current density goes up. According to analysis, it can be found that the copper nanoparticle can be obtained in smaller size, better dispersibility and narrower distribution of particle size under the current density of 0.01 A/cm2. At the same time, current density eventually affects the size of the nanoparticles as well as overpotential and the size of water droplet. © 2010 Inderscience Enterprises Ltd. Source
Liu Z.,Zhejiang University |
Liu Z.,Shaoxing Testing Institute of Quality Technical Supervision |
Feng G.,Zhejiang University |
Pan C.,Zhejiang University |
And 4 more authors.
Cuihua Xuebao/Chinese Journal of Catalysis
Biomass is a promising alternative for sustainable supply of precious intermediates and fine chemicals to the chemical industry. Lactic acid (2-hydroxypropanoic acid) and its related alkyl lactates are widely used in chemicals, food, pharmaceuticals, and cosmetic products. A study of the liquid-phase conversion of biomass-derived carbohydrates directly to methyl lactate catalyzed by Sn-MCM-41 and SnO 2/SiO 2 in subcritical methanol is presented. With glucose as substrate, methyl lactate yield reached 40.3% under the optimal reaction conditions. Fresh and used catalysts were characterized by X-ray diffraction, N 2 adsorption-desorption, transmission electron microscopy, infrared spectroscopy with pyridine adsorption, and NH 3 temperature-programmed desorption techniques. Methyl lactate yield was closely related to reaction temperature, reaction time, and the acidic site amount of catalysts. The catalysts were active and can be reused without significant decrease in the catalytic activity after being used for five recycles. The mesoporous structure and acid sites of the reused catalysts did not change much and the leaching of Sn was less than 0.15%. They were easy and relatively rapid synthesis, operational simplicity, reusability, and safe handling. Source
Zhang S.,Shaoxing University |
Zhang S.,Shaoxing Testing Institute of Quality Technical Supervision |
Yang S.,Shaoxing University |
Huang L.,Shaoxing University |
And 3 more authors.
Chinese Journal of Organic Chemistry
Cross-coupling reactions of aryl sulfonyl and sulfinate compounds have been well developed as an efficient synthetic method in recent years. Aryl sulfonyl chlorides, arylsulfinates and arylsulfonyl hydrazides have been used as desulfitative arylation, arylsulfonylation and reductive aryl sulfidation reagents in the synthesis of biaryls, aryl sulfones and aryl sulfides. The research progress on cross-coupling with aryl sulfonyl and sulfinate compounds combined with our work is reviewed, focusing on applications and progress in new synthetic method to construct carbon-carbon, carbon-sulfonyl and carbon-sulfur bond. © 2015 Chinese Chemical Society & SIOC, CAS. Source
Shen F.,Zhejiang University |
Ying Y.B.,Shaoxing Testing Institute of Quality Technical Supervision |
Xu H.R.,Shaoxing Testing Institute of Quality Technical Supervision |
Li B.B.,Shaoxing Testing Institute of Quality Technical Supervision
Transactions of the ASABE
It is well known that wine quality and value are closely related to the organoleptic characteristics developed during the aging process. Therefore, the correct characterization of wine aging status is of great commercial and scientific interest. In this study, Fourier transform near-infrared (FT-NIR) spectroscopy has been applied as a rapid tool for discrimination of different aging times (3, 9, 15, 21, 27, and 33 months) of Chinese rice wines aged in ceramic pots. The chemical compositions of rice wines were also determined to investigate the difference between samples of various aging times. Discrimination analysis was then carried out by principal component analysis (PCA), linear discriminant analysis (LDA), and partial least squares discriminant analysis (PLS-DA). The overall correct classification rates obtained by LDA and PLS-DA in the prediction were both 96.7%. The results demonstrate that NIR spectroscopy may be suitable for the identification of aging status of Chinese rice wine. © 2011 American Society of Agricultural and Biological Engineers ISSN 2151-0032. Source