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Two New Sesquiterpenes from Ligularia macrophylla

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Chinese Chemical Letters 2005年第9期16卷 1220-1222页

作者： Tong SHEN wei dong xie Zhong Jian JIA College of Chemistry and Chemical Engineering State key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000

Two new eremophilane sesquiterpenes, 15β-formic ether-6-oxo-furanoeremophilane （1） and 6α, 15β-epoxy eremophila-7（11）-en-8α, 12-olide （2） were isolation from the roots of Ligularia macrophylla. Their structu... 详细信息

关键词： Ligularia macrophylla Compositae eremophilane sesquiterpene

Microstructure, mechanical properties, and corrosion resistance of Mg–9Li–3Al–1.6Y alloy

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Rare Metals 2016年第5期35卷 374-379页

作者： Hao-Miao Yang Nan-Yi Zhang Na Liu wei-dong xie Xiao-dong Peng College of materials Science and Engineering Chongqing University School of Physics & Electron Engineering Yangtze Normal University

Mg–9Li–3Al–1.6Y alloys were prepared through mixture method. The microstructure, mechanical properties, and corrosion resistance of the as-cast and asextruded alloys were studied by optical microscopy（OM）,scanning electronic microscopy（SEM）, X-ray diffraction（XRD）, mechanical properties testing, and electrochemical measurement. The as-cast Mg–9Li–3Al–1.6Y alloy with the average grain size of 325 lm is composed of b-Li matrix, block a-Mg, and granule Al2Y phases. After extrusion, the grain size of the as-cast alloy is obviously refined and reaches to 75 lm; the strength and elongation of the extruded alloy are enhanced by 17.20 % and49.45 %, respectively, owing to their fine microstructure and reduction of casting defects. The as-extruded alloy shows better corrosion resistance compared to the as-cast one, which may be related to the low stored energy and dislocation density in the extruded alloy, also the homogenization treatment before extrusion.

关键词： Magnesium alloy Microstructures Mechanical properties Corrosion resistance

Petatrichol B: A Pentacyclic Triterpenoid with Unusual Skeleton from Petasites tricholobus

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Chinese Chemical Letters 2005年第10期16卷 1351-1353页

作者： wei dong xie Ping Lin LI Zhong Jian JIA College of Chemistry and Chemical Engineering National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000

A novel pentacyclic triterpenoid, petatrichol B, was isolated from the rhizome of Petasites tricholobus. Its structure was established by means of spectroscopic analysis （EIMS, HRSIMS, IR, 1D NMR and 2D NMR）.

关键词： Petasites tricholobus Compositae triterpenoid petatrichol B.

Landslides susceptibility mapping in Guizhou province based on fuzzy theory

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Mining Science and Technology 2009年第3期19卷 399-404页

作者： WANG wei-dong xie Cui-ming DU Xiang-gang School of Civil Engineering and Architecture Central South University Changsha Hunan 410075 China

The purpose of this study was to assess the susceptibility of landslides around the area of Guizhou province based on fuzzy *** first instance, slope, elevation, lithology, proximity to tectonic lines, proximity to drainage and annual precipitation were taken as independent, causal factors in this study.A landslide hazard evaluation factor system was established by classifying these factors into more subclasses according to some ***, a trapezoidal fuzzy number weighting(TFNW) approach was used to assess the importance of six causal factors to landslides in an ArcGIS ***, a landslide susceptibility map was created based on a weighted linear combination *** to this susceptibility map, the study area was classified into four categories of landslide susceptibility:low, moderate, high and very ***, in order to verify the results obtained, the susceptibility map and the landslide inventory map were combined in the *** addition, the weighting procedure showed that TFNW is an efficient method for weighting causal landslide factors.

关键词： landslides susceptibility mapping fuzzy theory GIS weighted linear combination

Two New Oplopanol Esters from Ligularia narynensis

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Chinese Chemical Letters 2006年第3期17卷 341-343页

作者： Xue GAO Tong SHEN wei dong xie Zhong Jian JIA College of Chemistry and Engineering State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000

Tow new oplopanol esters were isolated from the roots of Ligularia narynensis. Their structures were eluc idated by spectroscopic methods, especially 2D-NMR techniques.

关键词： Ligularia narynensis Compositae sesquiterpenoids oplopanol esters.

Time Dependence of Entropy Flux and Entropy Production of a Dissipative Dynamical System Driven by Non-Gaussian Noise

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Communications in Theoretical Physics 2008年第6期49卷 1561-1566页

作者： GUO Yong-Feng XU wei LI dong-Xi xie Wen-Xian Department of Applied Mathematics Northwestern Polytechnical University Xi＇an 710072 China

A stochastic dissipative dynamical system driven by non-Gaussian noise is investigated. A general approximate Fokker-Planck equation of the system is derived through a path-integral approach. Based on the definition of Shannon＇s information entropy, the exact time dependence of entropy flux and entropy production of the system is calculated both in the absence and in the presence of non-equilibrium constraint. The present calculation can be used to interpret the interplay of the dissipative constant and non-Gaussian noise on the entropy flux and entropy production.

关键词： information entropy entropy flux and entropy production non-Gaussian noise Fokker-Planck equation

Effects of Welding Speed and Post-weld Hot Rolling on Microstructure and Mechanical Properties of Friction Stir-Welded AZ31 Magnesium Alloy

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Acta Metallurgica Sinica(English Letters) 2018年第8期31卷 853-864页

作者： Gang Liu Li-Na Ma Zhen-Duo Ma Xue-Song Fu Guo-Bing wei Yan Yang Tian-Cai Xu wei-dong xie Xiao-dong Peng College of Materials Science and Engineering Chongqing UniversityChongqing 400044China National Engineering Research Center for Magnesium Alloys Chongqing 400044China

The as-rolled AZ31 Mg alloy sheets are welded by friction stir welding（FSW） in this study, followed by annealing and hot rolling with different reductions. The effects of welding speed and the rolling reduction on the microstructure, tensile properties, microhardness and fracture surfaces of the specimens are investigated. The results show that the microstructures of the FSW joint in different regions become more and more consistent as the hot rolling reduction increases. The mechanical properties of the FSW joints and the joint coefficient are improved with increasing rolling reduction; however,the hardness value in the stirred zone decreases firstly and then increases. When the rolling reduction is 50%, the tensile strength of FSW joint is close to that of base metal. The sample L_3 achieves the best comprehensive properties, with the yield strength, ultimate tensile strength and elongation of 162, 287.9 MPa, and 17.9%, respectively.

关键词： Magnesium alloy FSW Post-weld hot rolling Microstructure Mechanical properties

Striking a growth–defense balance:Stress regulators that function in maize development

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Journal of Integrative Plant Biology 2024年第3期66卷 424-442页

作者： Shiyi xie Hongbing Luo wei Huang weiwei Jin Zhaobin dong Maize Engineering and Technology Research Center of Hunan Province College of AgronomyHunan Agricultural UniversityChangsha 410128China State Key Laboratory of Maize Bio-breeding National Maize Improvement CenterFrontiers Science Center for Molecular Design BreedingChina Agricultural UniversityBeijing 100193China Tianjin Key Laboratory of Intelligent Breeding of Major Crops Fresh Corn Research Center of BTHCollege of Agronomy&Resources and EnvironmentTianjin Agricultural UniversityTianjin 300384China

Maize(Zea mays)cultivation is strongly affected by both abiotic and biotic stress,leading to reduced growth and *** has recently become clear that regulators of plant stress responses,including the phytohormones abscisic acid(ABA),ethylene(ET),and jasmonic acid(JA),together with reactive oxygen species(ROS),shape plant growth and *** their well established functions in stress responses,these molecules play crucial roles in balancing growth and defense,which must be finely tuned to achieve high yields in crops while maintaining some level of *** this review,we provide an in-depth analysis of recent research on the developmental functions of stress regulators,focusing specifically on *** unraveling the contributions of these regulators to maize development,we present new avenues for enhancing maize cultivation and growth while highlighting the potential risks associated with manipulating stress regulators to enhance grain yields in the face of environmental challenges.

关键词： stress regulators maize development ABA ET JA ROS

Fischelactone:A novel eremophilane dimer from Ligularia fischeri

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Chinese Chemical Letters 2010年第5期21卷 613-615页

作者： Hong Zhao Cheng Wu Weng Xin Tian Peng Xiang Lai Jian Jun Huang wei dong xie Marine College Shandong University at WeihaiWeihai 264209China College of Chemistry and Bioengineering Lanzhou Jiaotong UniversityLanzhou 730070China State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000China

A novel eremophilane dimer,named fischelactone（1）,was isolated from the roots of Ligularia *** structural elucidation of this compound was performed by HRESIMS,IR,1D NMR and 2D NMR（;H-;H COSY,HMBC,HMQC and NOESY） ... 详细信息

关键词： Ligularia fischeri Sesquiterpenoid Eremophilane dimer Fischelactone