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A New Dimeric Phthalide from Angelica sinensis

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Chinese Chemical Letters 2006年第12期17卷 1579-1581页

作者： ling YI Ping li Zhi ming BI Key Laboratory of Modem Chinese Medicines Ministry of Education and Department of Pharmacognosy China Pharmaceutical University Nanjing 210009

A new dimeric phthalide named Z, Z＇-3.3＇a, 7.7＇a-diligustilide was isolated from the roots of Angelica sinensis. Its structure was determined using spectroscopic methods and X-ray crystallographic diffraction analy... 详细信息

关键词： Angelica sinensis dimeric phthalide X-ray diffraction.

Efficient Synthesis of 3,5,6,8-Tetrahydro-4H-thiopyrano[4′,3′:4,5]· thieno[2,3-d]pyrimidin-4-ones via an Iminophosphorane

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Chemical Research in Chinese Universities 2010年第1期26卷 60-65页

作者： li Wen-jing liU Min FENG ling-ling DING ming-wu Key Laboratory of Pesticide ＆ Chemical Biology of Ministry of Education Central China Normal University Wuhan 430079 P. R. China

3,5,6,8-Tetrahydro-4H-thiopyrano[4＇,3＇：4,5]thieno[2,3-d]pyrimidin-4-ones（7） were synthesized via the base catalytic reactions of amines or phenols with carbodiimides（5）, which were obtained from the aza-Wittig ... 详细信息

关键词： 3,5,6,8-Tetrahydro-4H-thiopyrano[4',3':4,5]thieno[2,3-d]pyrimidin-4-one Aza-Wittig reaction Carbodii- mide Isocyanate

Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第01期 288-296页

作者： Shuai liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen ming-ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

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Does nature-based solution sustain grassland quality? Evidence from rotational grazing practice in China

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Journal of Integrative Agriculture 2023年第8期22卷 2567-2576页

作者： li Dong-qing ZHANG ming-xue Lü Xin-xin HOU ling-ling Institute of Agricultural Economics and Development Chinese Academy of Agricultural SciencesBejing 100081P.R.China China Center for Agricultural Policy School of Advanced Agricultural SciencesPeking UniversityBeijing 100871P.R.China

Rotational grazing is considered as one of the nature-based solutions(NbS)to grassland protection by natural ***,its effects on improving grassland quality are still unclear when it is adopted by *** a householdlevel panel data from field survey in two main pastoral provinces of China,empirical results from fixed-effect model and instrumental approach show that rotational grazing practices have insignificant short-term effects on grassland quality,but have positive long-term *** addition,rotational grazing practices can improve grassland quality when villages invest public infrastructure or herders have private supporting measures for more efficiency livestock *** analysis shows that herders adopting rotational grazing have higher grazing intensity,higher supplementary intensity and more livestock-house-feeding days,which indicate herders can utilize more efficient livestock management without increasing pressure on natural *** also find that herders with pastoral income are more likely to adopt rotational grazing *** insightful findings offer policy implications on promoting grassroot NbS for ecosystem protection and resource utilization in developing pastoral countries.

关键词： grassroots nature-based solutions rotational grazing grassland quality pastoral region China

Effect of Al2O3/TiO2/Na2O on enrichment of phosphorus in P-bearing steelmaking slag

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Journal of Iron and Steel Research International 2019年第8期26卷 796-805页

作者： Kan Yu Yan-ling Zhang Feng-shan li ming Gao State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China

To explore the influence of Al2O3/TiO2/Na2O on the mineralogical structure and phosphorus enrichment of converter slag, phosphorus enrichment and distribution in the CaO-SiO2-Fe2O3-MgO-Al2O3/TiO2/Na2O slag system were experimen-tally examined. The results show that phosphorus mainly exists in an n2CaO·SiO2-3CaO·P2O5 (nC2S-C3P) solid solution. Al2O3/TiO2/Na2O is beneficial for phosphorus enrichment in the CaO-SiO2-Fe2O3-MgO slag system to various degrees. This allows screening and separation of the enriched phase in the slag. When Al2O3 content was increased from 0 to 15%, the P2O5 content in the P-rich phase increased from 13.88 to 21.32%, and the area of the P-rich phase decreased from 57.50 to 37.87%. When the TiO2 content was increased from 0 to 10%, the content of P2O5 in the P-rich phase increased from 13.88 to 22.90%, and the area of the P-rich phase decreased from 57.50 to 39.20%. When the contents of Al2O3 and TiO2 were increased, the previously formed nC2S-C3P solid solution transformed into n′C2S-C3P (n lid solution gradually became Na2Ca4(PO4)2SiO4, and the area of the P-rich phase increased from 57.50 to 68.50%. With increasing the content of ATN (a mixture with a mass ratio of Al2O3/TiO2/Na2O = 15:4:3) from 0 to 30%, the content of P2O5 increased from 13.88 to 42.10% and the area of the P-rich phase decreased from 54.92 to 18.40%.

关键词： Phosphorus enrichment nC2S-C3P solid solution Modification P-bearing steelmaking slag

Material flow behavior and microstructural evolution during refill friction stir spot welding of alclad 2A12-T4 aluminum alloy

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International Journal of Minerals,Metallurgy and Materials 2021年第1期28卷 131-141页

作者： Gao-hui li li Zhou ling-yun Luo Xi-ming Wu Ning Guo State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Shandong Provincial Key Laboratory of Special Welding Technology Harbin Institute of Technology(WeihaiWeihai)264209China

In this study, we used the stop-action technique to experimentally investigate the material flow and microstructural evolution of alclad 2A12-T4 aluminum alloy during refill friction stir spot *** are two material flow components, i.e., the inward-or outward-directed spiral flow on the horizontal plane and the upward-or downward-directed flow on the vertical *** the plunge stage, the flow of plasticized metal into the cavity is similar to that of a stack, whereby the upper layer is pushed upward by the lower *** the refill stage, this is process *** such, there is no obvious vertical plasticized metal flow between adjacent *** leads to the coarsening of S(Al2CuMg) in the thermo-mechanically affected zone and the diminishing of S in the stir *** dynamic recrystallization results in the formation of fine equiaxed grains in the stir zone, but this process becomes difficult in the thermo-mechanically affected zone due to the lower deformation rate and the pinning action of S precipitates on the dislocations and sub-grain boundaries, which leads to a high fraction of low-angle grain boundaries in this zone.

关键词： refill friction stir spot welding aluminum alloy material flow behavior precipitate evolution dislocation configuration

Analysis of the Influence of the Blade Deformation on Wind Turbine Output Power in the Framework of a Bidirectional Fluid-Structure Interaction Model

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Fluid Dynamics & Materials Processing 2023年第5期19卷 1129-1141页

作者： ling Yuan Zhenggang liu li li ming lin CHN Energy United Power Technology Co. Ltd.Beijing100036China School of Energy and Power Engineering Shandong UniversityJinan250061China School of Renewable Energy North China Electric Power UniversityBeijing102206China

The blades of large-scale wind turbines can obviously deform during operation,and such a deformation can affect the wind turbine’s output power to a certain *** order to shed some light on this phenomenon,for which limited information is available in the literature,a bidirectional fluid-structure interaction(FSI)numerical model is employed in this *** particular,a 5 MW large-scale wind turbine designed by the National Renewable Energy Laboratory(NREL)of the United States is considered as a *** research results show that blades’deformation can increase the wind turbine’s output power by 135 kW at rated working *** with the outcomes of the simulations conducted using the model with no blade deformation,the results obtained with the FSI model are closer to the experimental *** is concluded that the bidirectional FSI model can replicate the working conditions of wind turbines with great fidelity,thereby providing an effective method for wind turbine design and optimization.

关键词： Wind turbine fluid-structure interaction numerical simulation blade

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高校验证型实验教学存在的问题与对策

广州化工 2020年第23期48卷 173-174,199页

作者：高华敏张杨高晓宝李明玲巢湖学院化学与材料工程学院安徽巢湖238000

针对当前高校验证型实验教学过程中存在的实验内容陈旧单一、教师投入不够学生兴趣不浓、认识不到位等问题,围绕实验内容的整合更新、实验方案的优化设计、实验方式方法的改进、强化实验教材建设和加强实验教学质量监控等方面提出了改... 详细信息

针对当前高校验证型实验教学过程中存在的实验内容陈旧单一、教师投入不够学生兴趣不浓、认识不到位等问题,围绕实验内容的整合更新、实验方案的优化设计、实验方式方法的改进、强化实验教材建设和加强实验教学质量监控等方面提出了改革措施,以培养学生学习兴趣、调动积极性,进而通过验证性实验为培养学生科学思维和创新能力奠定基础。

关键词：验证型实验教学教学改革创新能力

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构建体现专业特色的实践教学体系

实验科学与技术 2009年第6期7卷 110-112,121页

作者：李宏林李明玲万新军高晓宝巢湖学院化学与材料科学系巢湖学院新型功能材料与精细化学品研究所安徽巢湖238000

实践教学在整个教学过程中占有十分重要的地位,有着其他教学形式不可替代的作用。文章分析了巢湖学院化学与材料科学系无机非金属材料工程专业实践教学现状及存在的问题和不足,提出了构建一个体现无机非金属材料工程专业特色的实践教学... 详细信息

实践教学在整个教学过程中占有十分重要的地位,有着其他教学形式不可替代的作用。文章分析了巢湖学院化学与材料科学系无机非金属材料工程专业实践教学现状及存在的问题和不足,提出了构建一个体现无机非金属材料工程专业特色的实践教学体系的设想,为建设无机非金属材料工程特色专业提供理论和实践基础。

关键词：无机非金属材料工程实践教学体系构建专业特色