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Zhou Z.,Northeast Forestry University | Zhou Z.,Heilongjiang Academy of Forestry | Xu M.,Northeast Forestry University | Yang Z.,Northeast Forestry University | And 2 more authors.
Journal of Reinforced Plastics and Composites | Year: 2014

Chopped carbon fibers reinforced wood plastic composites were fabricated using a two-step extrusion process. As a coupling agent, maleic anhydride polyethylene was added for improving the interfacial adhesion between the chopped carbon fibers and plastic matrix. The results showed that the mechanical properties of the maleic anhydride polyethylene-added composites were significantly improved compared to that without maleic anhydride-grafted polyethylene. Tensile strength, flexure strength and impact strength were increased by 97%-133%, 113%-119% and 181%-251%, respectively, which were very close to the strengths of structural timber. The adding of maleic anhydride polyethylene also influenced the electrical property of chopped carbon fibers reinforced wood plastic composites. The volume electrical resistivity of the composites with maleic anhydride polyethylene was higher. The scanning electron microscopy was used to examine the morphology of brittle fracture cross-section paralleled to the extrusion direction. It was observed that the interfacial adhesion was improved with the incorporation of maleic anhydride polyethylene. Chopped carbon fibers were coated by high-density polyethylene and the bonding connections were formed on the fiber surfaces. The distribution direction of chopped carbon fibers was parallel to the extrusion direction and dispersed more uniformly in the maleic anhydride polyethylene-added composites. © The Author(s) 2014. Source

Wang S.,Wildlife Institute of Heilongjiang Province | Xu F.-B.,Heilongjiang Academy of Forestry | Zhu L.-F.,Wildlife Institute of Heilongjiang Province | Yu Y.-Z.,Wildlife Institute of Heilongjiang Province | Na C.-Z.,Wildlife Institute of Heilongjiang Province
Advanced Materials Research | Year: 2013

The aim of this work was to determine the inhibitory effect of deer blood hydrolysates addition on lipid oxidation, color deterioration and microbial contamination of ground beef during during 9 days of refrigerated storage. The pH value, total plate count, thiobarbituric acid-reactive substances value (TBARS), total volatile basic nitrogen (TVB-N) and color were also determined. The results showed that the treatments added hydrolysates had significant inhibitory effects on lipid oxidation and kept the red color of ground beef in 9 days, when compared with controls (P < 0.05). Furthermore, the inhibitory effect enhanced as the adding level of the hydrolysates increased (P < 0.05). These results suggest that deer blood hydrolysates are good source of natural antioxidants. © (2013) Trans Tech Publications, Switzerland. Source

Wang Y.C.,Northeast Forestry University | Qu G.Z.,Northeast Forestry University | Li H.Y.,Heilongjiang Academy of Forestry | Wu Y.J.,Northeast Forestry University | And 3 more authors.
Molecular Biology Reports | Year: 2010

Superoxide dismutases (SODs) play important role in stress tolerance of plants. In this study, an MnSOD gene (TaMnSOD) from Tamarix androssowii, under the control of the CaMV35S promoter, was introduced into poplar (Populus davidiana 9 P. bolleana). The physiological parameters, including SOD activity, malondialdehyde (MDA) content, relative electrical conductivity (REC) and relative weight gain, of transgenic lines and wild type (WT) plants, were measured and compared. The results showed that SOD activity was enhanced in transgenic plants, and the MDA content and REC were significantly decreased compared to WT plants when exposed to NaCl stress. In addition, the relative weight gains of the transgenic plants were 8- to 23-fold of those observed for WT plants after NaCl stress for 30 days. The data showed that the SOD activities that increased in transgenic lines are 1.3-4-folds of that increased in the WT plant when exposed to NaCl stress. Our analysis showed that increases in SOD activities as low as 0.15-fold can also significantly enhance salt tolerance in transgenic plants, suggesting an important role of increased SOD activity in plant salt tolerance. © Springer Science+Business Media B.V. 2009. Source

Yin D.,Northeast Forestry University | Deng X.,Heilongjiang Academy of Forestry | Song R.,Northeast Forestry University
Journal of Forestry Research | Year: 2016

Korean spruce (Picea koraiensis Sieb. El Zucc.) is one of the main afforestation species in northern China. Seedling quality is a critical factor at planting time. To test whether the synergistic growth enhancement of Scotch pine (P. sylvestris var. mongolica) seedlings brought by the plant beneficial fungus Trichoderma virens (J.H. Mill., Giddens and A.A. Foster) Arx and ectomycorrhizal fungus (Suillus luteus (L.) Roussel.) can also benefit Korean spruce seedlings, we examined the effects of S. luteus and T. virens on the growth of P. koraiensis seedlings and drought resistance of P. sylvestris var. mongolica in peat soils. The two fungi were added to sterilized peat soil in pots, and the plants were grown for 4 months. Seedling growth and physiological variables, including mycorrhizal colonization rate of roots, biomass, and chlorophyll content, were examined. The colonization rate of the mycorrhizal fungus on P. koraiensis exceeded 65 %, and the synergism between S. luteus and T. virens enhanced most of the variables for P. koraiensis seedlings after inoculation with S. luteus then 30 days later with T. virens as in our published results for seedlings of P. sylvestris var. mongolica. When seedlings of P. sylvestris var. mongolica were inoculated with this sequence, they became more drought tolerant. T. virens also induced S. luteus to produce -1,3-glucanase and chitinase. This inoculation sequence at planting can thus improve the quality of P. sylvestris var. mongolica and P. koraiensis seedlings and substantiates our previous results. © 2015, Northeast Forestry University and Springer-Verlag Berlin Heidelberg. Source

Qin K.-L.,Northeast Forestry University | Guo F.-T.,Fujian Agriculture and forestry University | Di X.-Y.,Northeast Forestry University | Sun L.,Northeast Forestry University | And 3 more authors.
Chinese Journal of Applied Ecology | Year: 2014

This study chose zero-inflated model and Hurdle model that have been widely used in economic and social fields to model the fire occurrence in Tahe, Daxing'an Mountain. The AIC, LR and SSR were used to compare the models including zero-inflated Poisson model (ZIP), zero-inflated negative binomial model (ZINB), Poisson-Hurdle model (PH) and negative Binomial Hurdle (NBH) (two types, four models in total) so as to determine a better-fit model to predict the local fire occurrence. The results illustrated that ZINB model was superior over the other three models (ZIP, PH and NBH) based on the result of AIC and SSR tests. LR test revealed that the negative binomial distribution was suitable to both the "count" portion of zero-inflated model and hurdle model. Furthermore, this paper concluded that the zero-inflated model could better fit the fire feature of the study area according to the hypotheses of the two types of models. Source

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