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Structure identification for compound I separated and purified from taxoids-produced endophytic fungi (Alternaria. alternata var. taxi 1011)
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作者 项勇 刘君 +1 位作者 呂安国 崔京霞 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期217-220,共4页
Endophytic fungi are widely found in almost all kinds of plants. Many endophytic fungi can produce some physio-logical active compounds, which are same to or analog to those isolated from their hosts. Producing physio... Endophytic fungi are widely found in almost all kinds of plants. Many endophytic fungi can produce some physio-logical active compounds, which are same to or analog to those isolated from their hosts. Producing physiological active com-pounds through microbial fermentation can give a new way to resolve resource limitation and to find out alternative source. Through the methods of organic solvent extraction, thin layer chromatography (TLC) and column chromatography, compound I was isolated, purified from the liquid fermentation metabolites of the taxoids-produced endophytic fungi (Alternaria. alternata var. taxi 1011 Y. Xiang et LU An-guo) that was screened from the bark of Taxus. cuspidata Sieb.et Zucc.. Compound I was identified as one kind of taxoids type III, based on the analyzing results by using the methods of ultraviolet spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR). This study provides a com-pleted method for separation and purification of the endophytic fungi as well as structure identification of its fermentation me-tabolite 展开更多
关键词 Alternaria. Alternata var. taxi 1011 TAXOIDS Separation Purification structure identification
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Structure identification of an uncertain network coupled with complex-variable chaotic systems via adaptive impulsive control 被引量:1
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作者 刘丹峰 吴召艳 叶青伶 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第4期183-190,共8页
In this paper, structure identification of an uncertain network coupled with complex-variable chaotic systems is in- vestigated. Both the topological structure and the system parameters can be unknown and need to be i... In this paper, structure identification of an uncertain network coupled with complex-variable chaotic systems is in- vestigated. Both the topological structure and the system parameters can be unknown and need to be identified. Based on impulsive stability theory and the Lyapunov function method, an impulsive control scheme combined with an adaptive strategy is adopted to design effective and universal network estimators. The restriction on the impulsive interval is relaxed by adopting an adaptive strategy. Further, the proposed method can monitor the online switching topology effectively. Several numerical simulations are provided to illustrate the effectiveness of the theoretical results. 展开更多
关键词 structure identification NETWORK complex-variable chaotic system impulsive control
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Structure elucidation,immunomodulatory activity,antitumor activity and its molecular mechanism of a novel polysaccharide from Boletus reticulatus Schaeff 被引量:7
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作者 Siyuan Su Xiang Ding +3 位作者 Yiling Hou Binbin Liu Zhouhe Du Junfeng Liu 《Food Science and Human Wellness》 SCIE CSCD 2023年第2期647-661,共15页
A new water-soluble heteropolysaccharide with a molecular weight of 15 k Da was isolated from the fruiting bodies of Boletus reticulatus Schaeff.Structural characterization results revealed that B.reticulatus Schaeff ... A new water-soluble heteropolysaccharide with a molecular weight of 15 k Da was isolated from the fruiting bodies of Boletus reticulatus Schaeff.Structural characterization results revealed that B.reticulatus Schaeff polysaccharide(BRS-X)had a backbone of 1,6-linkedα-D-galactose and 1,2,6-linkedα-D-galactose which branches were mainly composed of a terminal 4-linkedβ-D-glucose and the ratio of D-galactose and D-glucose was 5:1.Bioactivity assays indicated that BRS-X displayed a strong proliferative activity in T cells and B cells and promoted the secretion of immunoglobulin G(Ig G),Ig E,Ig D and Ig M.In addition,BRS-X could facilitate the proliferation and phagocytosis of RAW264.7 cells and could significantly inhibit the growth of tumors in S180-bearing mice.The results of transcriptome sequencing analysis illustrated that total 46 genes enriched in MAPK and total 34 genes enriched in PI3 K/Akt signaling pathways in BRS-X group.The protein VEGF and VEGFR expression were significantly reduced under the treatment with BRS-X.These findings provide a scientific basis for the edible and medicinal value of BRS-X. 展开更多
关键词 Boletus reticulatus Schaeff POLYSACCHARIDES structure identification Immunomodulatory activity Antitumor activity
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Composition and antioxidant activity of anthocyanins isolated from Yunnan edible rose(An ning) 被引量:13
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作者 Qin Ge Xiaojun Ma 《Food Science and Human Wellness》 SCIE 2013年第2期68-74,共7页
Edible roses(An ning)are a good source of anthocyanins and grown widely in Yunnan Province of China.In this study,the contents of anthocyanins and total phenol as well as the antioxidant activity of methanol extract f... Edible roses(An ning)are a good source of anthocyanins and grown widely in Yunnan Province of China.In this study,the contents of anthocyanins and total phenol as well as the antioxidant activity of methanol extract from specific variety of rose were systematically investigated.The results showed that anthocyanins and total phenolic content of the petals were(353.56±2.50)mg cyanidin 3,5-diglucoside(Cy-3,5-diglu)equivalents and(2087.43±17.37)mg gallic acid equivalents(GAE)per 100 g fresh weight(FW),respectively.Totally,3 kinds of anthocyanins were detected and Cy-3,5-diglu was the predominant constituent which accounted for approximately 94.9%of total anthocyanins according to the analysis results of high performance liquid chromatography-photodiode array detection(HPLC-PAD).Data demonstrated that the extract from edible rose exhibited excellent ferric reducing capacity and free radical scavenging activity against both 2,2-diphenyl-1-picrylhydrazyl(DPPH)and 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt(ABTS).The equivalents of anthocyanins from roses on DPPH,ABTS and ferric reducing ability were 2089,639 mg and 1400 mg GAE per 100 g FW,respectively.The high anthocyanins content and excellent antioxidant activity suggested that Yunnan edible roses could be applied in food industry as a good source of natural pigments.©2013 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved. 展开更多
关键词 Yunnan edible rose Anthocyanins structure identification Antioxidant activity
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Super deformability and thermoelectricity of bulkγ-InSe single crystals 被引量:4
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作者 Bin Zhang Hong Wu +7 位作者 Kunling Peng Xingchen Shen Xiangnan Gong Sikang Zheng Xu Lu Guoyu Wang Xiaoyuan Zhou 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第7期570-577,共8页
Indium selenide,aⅢ–Ⅴgroup semiconductor with layered structure,attracts intense attention in various photoelectric applications,due to its outstanding properties.Here,we report super deformability and thermoelectri... Indium selenide,aⅢ–Ⅴgroup semiconductor with layered structure,attracts intense attention in various photoelectric applications,due to its outstanding properties.Here,we report super deformability and thermoelectricity ofγ-In Se single crystals grown by modified Bridgeman method.The crystal structure of In Se is studied systematically by transmission electron microscopy methods combined with x-ray diffraction and Raman spectroscopy.The predominate phase ofγ-In Se with dense stacking faults and local multiphases is directly demonstrated at atomic scale.The bulkγ-In Se crystals demonstrate surprisingly high intrinsic super deformative ability which is highly pliable with bending strains exceeding12.5%and 264%extension by rolling.At the meantime,In Se also possesses graphite-like features which is printable,writable,and erasable.Finally,the thermoelectric properties ofγ-In Se bulk single crystals are preliminary studied and thermal conductivity can be further reduced via bending-induced defects.These findings will enrich the knowledge of structural and mechanical properties'flexibility of In Se and shed lights on the intrinsic and unique mechanical properties of In Se polytypes. 展开更多
关键词 γ-InSe single crystals structure identification super deformability thermoelectric properties
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Operational Modal Analysis of a Ship Model in the Presence of Harmonic Excitation 被引量:1
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作者 Junchen Xu Ming Hong Xiaobing Liu 《Journal of Marine Science and Application》 2013年第1期38-44,共7页
A ship is operated under an extremely complex environment, and waves and winds are assumed to be the stochastic excitations. Moreover, the propeller, host and mechanical equipment can also induce the harmonic response... A ship is operated under an extremely complex environment, and waves and winds are assumed to be the stochastic excitations. Moreover, the propeller, host and mechanical equipment can also induce the harmonic responses. In order to reduce structural vibration, it is important to obtain the modal parameters information of a ship. However, the traditional modal parameter identification methods are not suitable since the excitation information is difficult to obtain. Natural excitation technique-eigensystem realization algorithm (NExT-ERA) is an operational modal identification method which abstracts modal parameters only from the response signals, and it is based on the assumption that the input to the structure is pure white noise. Hence, it is necessary to study the influence of harmonic excitations while applying the NExT-ERA method to a ship structure. The results of this research paper indicate the practical experiences under ambient excitation, ship model experiments were successfully done in the modal parameters identification only when the harmonic frequencies were not too close to the modal frequencies. 展开更多
关键词 natural excitation technique (NExT) eigensystem realization algorithm (ERA) ship structure harmonic excitation signal processing modal parameters identification ship model operational model analysis
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