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951.
HE Youjun CUI Guofa FENG Zongwei.Research Institute of Forestry Policy Information Chinese Academy of Forestry Beijing P.R. China. College of Resources Environment Beijing Forestry University Beijing P.R..China. Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing P.R..China 《中国林业科技(英文版)》2005,4(3):29-36
INTRODUCTIONA large number of nature resources have fosteredhuman beings in the world. However, during the lastfew decades these nature resources and biodiversitywere subjected to various anthropogenic pressuressuch as plantation, deforestation, construction ofhydro-electric project, overgrazing and exploitation andother developmental activities (He Youjun, et al, 2004b;Li Ang, et al, 2002; Swamy, et al, 2000). In order toprotect environment and biodiversity, we have to facethe challenge… 相似文献
952.
CHANG Delong SONG Zhanqian HU Weihua HUANG WenhaoLI Fuhai ZHANG Yunling. Paulownia Research Center of China Zhengzhou P.R.China. Research Institute of Chemical Processing Utilization of Forest Productsof Chinese Academy of Forestry Nanjing P.R.China 《中国林业科技(英文版)》2006,5(1):1-7
INTRODUCTIONPaulownia is one of important species with fastgrowth and high yield oriented to industry uses inChina, paulownia wood is widely used in furniture-making, decorating materials, musical instrumentsmanufacture (Jiang Jianping 1990), etc. Brown orblack stain often appears on the surface of paulowniawood during processing and using. Discolorationseriously affects paulownia utilization, and it cancause huge loss due to low grade and price causedby stain (Cheng Junqing 1983a, 1983b… 相似文献
953.
LIU Tao ZHANG Huaxing Institute of Forestry Chinese Academy of Forestry Beijing P. R. China 《中国林业科技(英文版)》2005,4(2):8-14
INTRODUCTIONBecause of the interleaving, extensity of multi-factorsaffecting forest ecological benefit in space, and thecomplexity of bio-factors of forest,and in themeantime, because of lacking of consultation forthe transformation between physical and ecologicalquantum and monetary value, the evaluation ofecological benefit of forest is all along one of thedifficult problems in academic field. In recent years,some scholars have made much research andexploration in the theory and practice… 相似文献
954.
Sarin R 《Fitoterapia》2004,75(1):62-64
The callus tissue of Tagetes erecta maintained on revised Murashige and Skoog's medium (RT) as static cultures showed the presence of insecticidal pyrethrins. The percentage of pyrethrins further increased by feeding the tissue with various concentrations of ascorbic acid. The maximum pyrethrin content (1.68%) was observed in 6 weeks old tissue grown on RT medium supplemented singly with 1000 mg/l of exogenous ascorbic acid. When pyrethrin mixture was screened against Tribolium spp. immediate 'knock down' effect was observed. 相似文献
955.
A methanolic extract of Ravenia spectabilis, an isolated alkaloid, arborinine plus a fraction comprising arborinine and gamma-fagarine (VLC), showed mild to significant in vitro antibacterial activity. In a brine shrimp lethality bioassay, the extract and the fraction were found to exhibit moderate cytotoxicity having LC50 of 76.26 microg/ml and 14.98 microg/ml, respectively. 相似文献
956.
The methanol and ethyl acetate extracts of the aerial parts of Cirsium tenoreanum, have been evaluated for their phytochemical constituents and antibacterial and cytotoxic properties. Three flavonoids, apigenin, quercetin-3-O-galactoside and kaempferol-3-O-ramnoside, were isolated. The ethyl acetate extract showed a good antiproliferative activity. 相似文献
957.
After reviewing the present status and prospects of wood industry in the world, the author suggests that in response to the new situation of economic globalization and China's entry into the WTO, the Chinese wood industry should further develop IT application, optimize and upgrade industrial structure and raise quality of labor force, blazing a new trail to industrialization featuring high scientific and technological content, good economic return, low resources consumption, little environmental pollution and a full display of advantages in human resources, so as to enhance its international competitiveness to supply customers better products and services at lower cost. 相似文献
958.
959.
Basile A Sorbo S Giordano S Ricciardi L Ferrara S Montesano D Castaldo Cobianchi R Vuotto ML Ferrara L 《Fitoterapia》2000,71(Z1):S110-S116
Following the extraction of Castanea sativa with an aqueous solution of sulfuric acid (pH 3.0), the ethyl acetate soluble fraction was tested for its antibacterial and allelopathic activity. The extract was shown to have pronounced antibacterial effects against seven of the eight strains of Gram-positive and Gram-negative bacteria used (MIC in the range of 64-256 microg/ml and MBC in the range of 256-512 microg/ml). The active fraction was analyzed by TLC and HPLC showing the presence of rutin, hesperidin, quercetin, apigenin, morin, naringin, galangin and kaempferol. Standards of the identified flavonoids were tested against the same bacterial strains. The highest activity was shown by quercetin, rutin and apigenin. The allelopathic effect was tested against Raphanus sativus seed germination. The extract, quercetin, rutin and apigenin caused a decrease in the percentage of seed germination and root and epicotyl growth. 相似文献