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The generally accepted that Zipf-Distribution is a convinced access pattern for text-based Web. However, with the dramatic increasement of VoD media traffic on the Internet such as Flash P2P, the inconsistency between the access patterns of media objects and the Zipf model has been researched by many scholars. In this paper, we have studied a large variety of media work-loads collected from both browser and server sides in Adobe Flash P2P systems which applied in Youku, Youtube, etc. Through extensive analysis and modeling. And found the object reference ranks of all these workloads follow the logistic (LOG) distribution despite their different media systems and delivery methods by extensive analysis and modeling. This mean it does not follow long tail effect; Furthermore, we have constructed mathematical models which can applied in access pattern in FlashP2P traffic. By analyzing the model of media traffic access, it is possible to better describe the user’s access mode. Meantime, it is very suitable for the configuration and allocation of network resources which can be used more efficiently.

Phytochemical investigation of the stem of Syringa pinnatifolia Hemsl led to the isolation of 13 lignans (4–12, 14–17) and four phenolic compounds (1–3, 13), in which a new lignan (14) was isolated from this plant and compounds 5 and 6 were found for the first time in the genus Syringa. Lignans are major compounds in this plant, which may be used as chemotaxonomic markers for the genus Syringa.

An investigation of ethyl acetate extracts from Syringa pinnatifolia has led to the isolation of one new lignan (1) together with three known compounds (2–4). The structures of compounds 1–4 were identified by UV, IR, ESI-MS, and 1D NMR and 2D NMR. 2,2-Diphenyl-1-picryhydrazyl (DPPH) was used to evaluate the antioxidant activity of the compounds for the radical scavenging capacity. All of the compounds showed strong antioxidant activity.

A new megastigmane glycoside, together with two known compounds, has been isolated from the flowers of Hosta plantaginea. The structure elucidation of the new compound was carried out by 1D (1H and 13C NMR) and 2D NMR (COSY, HSQC, HMBC, and NOESY) spectral analysis. The antibacterial and antioxidant activities of the three compounds were evaluated against various bacteria, and their radical scavenging capacity was evaluated using 2,2-diphenyl-1-picryhydrazyl (DPPH).

Flavonoid and biflavonoid glycosides have been isolated from the n-BuOH extract of Artemisia frigida Willd. This is the first report on the structure elucidation of two new compounds based on spectroscopic methods including ultraviolet (UV), infrared (IR), ESI–MS, 1D and 2D NMR techniques. The new compounds were investigated for their effect against inflammation induced by egg albumin and carrageenan in rats. .

An investigation of the EtOAc-soluble fraction from the aerial parts of Artemisia frigida Willd.(A. frigida) led to the isolation of three new flavonoid glycosides together with three known compounds. Their structures were elucidated by spectral experiments. At the same time, high-performance liquid chromatographic(HPLC) method was used for the simultaneous determination of the six flavonoid glycosides from the aerial parts of A. frigida. The separation by gradient elution was performed on a Hypersil ODS-2 column(250 mm×4.6 mm, 5 μm) at 30 °C with acetonitrile and water as the mobile phase, and monitored by absorbance at 276 nm. The parameters of linearity, precision, accuracy and specificity of the method were evaluated. The recovery of the method is 96.50%–98.01%, and linearity(r>0.9992) was obtained for all the flavonoid glycosides. A high degree of specificity as well as repeatability and reproducibility(relative standard deviation values less than 2.0%) were also achieved. This assay was applied to the determination of six flavonoid glycosides in ten samples. The results indicate that the developed assay method was rapid, accurate, reliable and could be readily utilized as a quantitative analysis method for A. frigida.