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Synthetic biopolymer blends are gaining interest in the packaging industry because the incorporation of natural materials imparts biodegradable properties to films. In this study, polyethylene/chitosan (chitosan) films with thicknesses of about 0.3 ± 0.01 mm were fabricated via compression molding. The effects of the variation in the length of compounding as a function of the length/diameter (l/d) ratio (15:1, 30:1, 45:1, 60:1, and 75:1) were investigated. The experimental results show that a higher degree of miscibility of the blends was achieved with increasing compounding length; this led to improved mechanical properties in the films, and this was verified by the statistical analysis of data with the analysis of variance procedure. The tensile strength (TS) increased by about 25%, whereas the elongation at break (Ebreak) increased by twofold. Films fabricated from blends compounded with an l/d ratio of 60:1 had the highest TS and Ebreak values, and the TS was comparable to that of low-density polyethylene films. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43796.

Using hyperspectral technology to test canopy of the fir which was damaged by the anthracnose, exploring and built the hyper-spectral estimation models of the pigment content in canopy of Chinese fir under the disease stress, the results will promote the application of the hyper-spectral remote sensing-technology in the forest pest and disease monitoring. From May to July in 2012, You Xian, Hunan Province, we investigated the anthracnose of Chinese fir, and measured the canopy pigment content and the spectral reflectance of the Chinese fir which was damaged by the anthracnose. The correlation between pigment contents of fir leaves with spectra reflectance, the first derivative of reflectance and spectral characteristic parameters were analyzed respectively. The result showed that the visible light and near-infrared region were the sensitive region which were reflected and absorbed by the pigment in disease of Chinese fir; pigment content had the highest correlation with the first order differential spectra in red edge (695–754 nm), and the correlation coefficient of single band first order differential spectrum in 741 nm was the largest. And it also showed that the accuracy of Chla+b, Chla and Chlb contents was the highest estimated by power function model which used the difference vegetation index DVI [FD587,FD741] as the variable, the relative errors were less than 15%, the RMS error was in the range of 0.093 to 0.241.

Ginkgo is a genus of highly unusual non-flowering plants with one extant species. The Ginkgoaceae is a family of gymnosperms which appeared during the Mesozoic Era, of which the only extant representative is Ginkgo biloba, which is for this reason sometimes regarded as a living fossil. Extracts of Ginkgo contain flavonoid glycosides and terpenoids (ginkgolides, bilobalides) and have been used pharmaceutically. Polysaccharides of G. biloba can reduce blood sugar, immune regulation, antioxidation, anti-inflammatory effects and play an important role in anti-tumor effects. At present, the method of water extraction and alcohol precipitation was generally used for the extraction of polysaccharides from G. biloba. The de-protein methods of polysaccharides were Savag’s and trichloroacetic acid method. The extracted polysaccharides were generally a mixture and usually use a combination of two or more methods to separate from proteins and other contaminants to yield pure polysaccharides. The commonly used methods for purification were the step-by-step precipitation, salting-out and column chromatography method. Polysaccharides of G. biloba were polymers of glucose, rhamnose, arabinose, mannose, galactose and xylose. In this review, we summarized previous and current researches on polysaccharides from G. biloba and provide new insights for future work on polysaccharide of this specie. Key words: Polysaccharides, Ginkgo biloba, biological activity, chemical constituent.